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Got a bit of a question for you, I am currently fixing up a head for my Isuzu Trooper 3.1 turbo diesel engine (new valve guides, exhaust valves etc), have been cleaning up rough patches in the ports. I have noticed the valve seats protrude a ways into the ports, the portion that does protrude is rounded. Being that I am cleaning up the ports, will this be a problem for air flow?. Cheers.
Hey, I hate to do this… The comment section mechanics and safety warriors usually drive me crazy. But this piece of advice is coming directly from a heavy equipment mechanic with direct experience on what I'm about to say lol: earlier this week I was pounding in wheel seals with my seal driver, and the head is all mushroomed over. On the third seal, I hit the driver and a chunk of that mushroom piece flew off and hit me in the face. It actually drew blood. Never had that happen before. So I see your valve seat installing tool looks just like my seal installing tool and I was thinking you might wanna grind that down a little bit so you don't end up eating a piece of that like I did lol.. nice job on the diagnostics and tear down on this. Really interesting issue that came up with this engine. I like how thorough you guys are.
I was taught to grind off mushrooming heads back in HS metals shop and have religiously attended to any tool began to mushroom takes less than 10 seconds Weird the things that stick with you
@@bigj231 Sure is! I've had pieces of punches and chisels hit me in the face as well. Never pleasant! Thankfully, I've become a little bit smarter over the years. I've started wearing safety glasses & face shields much more often, when I know I'll be striking on things up close. Other things to be very cautious around are grinding wheels and cut off wheels. I have a small piece of a 4.5"dia fiberglass cut off wheel stuck in my cheek to this very day. It's crazy, because I can still remember it like yesterday, and it was easily a decade ago now. I remember the stinging pain, and thinking that I was glad I had safety glasses & my N95 dust mask on. I remember going to the bathroom to look in the mirror, once I had realized I was bleeding. Washed the blood off my face, put a little bit of Neosporin & a Band-Aid on it, and went back to work. Never thought about it again, as I never realized that something was actually still stuck in my cheek, at the point of the wound. I was reconstructing & fabricating a 53' van trailer's 5th wheel pin & plate crossmembers & flooring structure. A ton of cutting, grinding, & welding going on. Anyhow, I never knew there was a piece of grinding wheel still lodged in my face until the ER doctors did a full body scan of me, after I was in a severe pickup truck accident. The doctors were baffled by what the strange white spot was in my cheek, in their scan picture of my skull & face. Upon discussion, they even physically re-inspected my teeth & face. We then continued to discuss, until they concluded that what had happened to me years prior was the most likely cause of the unknown spot. LOL, so crazy! They said that if it doesn't bother me, best to just leave it alone. Any additional intrusions at this point could just scar up and potentially cause unwanted problems to my face. Point is, safety precautions sure can be a royal PITA sometimes, but the injuries they can prevent sure do make their use worthwhile.
Base engine Engineer from Cummins here, the connecting rod oil drilling feeding the small end was eliminated as it turns out it actually doesn't feed the small end with oil. The movement of the rod and alignment of the oil drillings ends up being such that the hole fills up with oil, but doesn't end up delivering a flow of oil to the bushing. The rotation of the connecting rod is to move that slot away from the loaded zone of the bearing during rotation. The slot takes away from effective bearing area, and increases wear of the bearing, so while not critical, it's very beneficial to have them rotated the correct orientation. Nice build! Really enjoy the videos!
I appreciate your style and delivery. I am not a mechanic, but 67 years of farm and trucking experience, I found this episode very informative, in particular the discussion of cavitation of the cylinder walls. Your on-screen presence conveys a trust-worthy, calm, steady manner - not a fast-paced state-fair huckster selling ginsu knives. You both convey believability, and welcoming discussion about the topic at hand - in other words a couple of guys we would love to lean against the workbench and hoist a beverage or two with on a late afternoon. Cheers!
Perfectly stated! I also appreciate their father/son relationship. I didn’t enjoy such a relationship with my father but I used that experience to make sure my two sons don’t grow up the same way as I did.
I love this channel - I feel like I'm in the shop as they have their very folksy discussion, giving clear explanations and shots of what (and how) they found while sharing their insightful conclusions. Both men are so humble as they talk about the task at hand and the pros and cons of what viewers wrote. Nicholas found the way to keep me from forwarding through the promotion by showing he and Jim continuing work on the project while pitching the sponsor. Excellent job ... thank you for sharing with us!
Don't you just love a good mechanical mystery series? It's like a game of Clue. Was it the butler with bad fuel, was it injection pump not to specifications. Or was it made in China, China?
As a fellow engine builder and diagnostition, I absolutely love your mission and style of delivery. Keep up the great content!! We never quit learning.....
I bet that pump being 20% over was the biggest cause of the problem. Because Allison had to see a problem with it for them to add piston coolers in the later model that were only slightly high Horsepower tractors. That's just my theory.
I would expect that if over fueling by the pump were the problem it would have been present in all the cylinders, not just a few with the other, good pistons looking perfect.
Have you guys thought about running an EGT probe and gauge to help keep an eye on the engine? I would think it would be a worth while investment considering all the issues you've had and work you've put into this tractor.
I love watching father and son do stuff together, that is awesome. It really misses my dad. I hope he's having a good time and heaven. This is one of the main things I miss. I am doing stuff like this with my father. Hold on to it. It will be the best memories when he's not there.
I'm gonna SWAG an idea. Add a braided ground strap from the block to chassis ground...make sure it's not bolted over paint! Also, was the oil cooler clear for coolant flow?
What a fantastic video guys. I could listen to your dad and you as well, explain things all day. I still say he should be a teacher, there's not many good ones left.
The cam ring in the pump was flipped. Shame it was missed when it was torn apart but I guarantee that’s why it was 180* out. If the new shop built the pump right this time it should be fine even with 20% more fuel.
Injecting fuel too early will overheat pistons just as preignition (over advanced spark) will damage a gasoline engine. Injecting too much fuel into a diesel just makes it run faster.
That valve being pushed up like that is called tuliping. Steve Morris had an engine that had this issue a while ago. Great explanation of what you guys have seen from the autopsy from Allis. Joe
Well done on a very good failure analysis. Think your fuel pump build is definitely your cause. Might be a good idea to spill time the pump when fitting it and volume check the injectors before fitting them
Liquid dye penetrant. This is Type 2, method C, form D. Always pre-clean the part you're going to inspect with the solvent that comes in the kit. Allow it to dry for about 20 minutes. Spray the penetrant on the area of interest and let it dwell for 10 minutes minimum. Wipe off the excess using a lint free cloth to remove the bulk penetrant, followed by a solvent dampened lint free cloth. Never spray solvent on the part to remove the excess penetrant or you will remove the penetrant from the defect and ruin you ability to detect it. Let the solvent evaporate for 10 minutes. Apply the non-aqueous developer by spraying in short bursts to just mist the part. Do not overapply the developer. Let it dwell for 10 minutes minimum and evaluate. Pre-cleaning removes the organic material (oil, grease, etc). This will allow the penetrant to fill the crack. A better inspection method is magnetic particle inspection. This method only works on ferrous materials. Cleaning is not as important.
Suggestion - when you start the engine check the manifold exhaust temperature with a pyrometer or heat gun for over-fuelling - especially under load, also Have you checked that you have the correct nozzles in the injectors and that they are set to the correct pressures / spray pattern?
I would recommend installing a pyrometer to monitor exhaust temps? Since I didn’t hear you mention it, are you using coolant with DCA or SCA additives for Diesel engines? It probably wouldn’t have prevented the liner putting in your case, it is necessary for long term. Just my 2 cents, for what it’s worth. Keep up the good work, I really enjoy your vids.
Maybe I missed you talking about it, but have you run the injectors on a test stand? The pump may have been turned up some but that wouldn't have been as big an issue as if an injector was over fueling.
When I was at UNOH for auto/diesel in ‘82/3. We talked a lot about the prevalence of cavitation in diesel’s. The explanation we were taught was also mechanical vibration as a primary cause but also coolant quality and chemistry. Aeration is a common factor. A comment mentioning grounding straps seems good advice also as cathodic corrosion can occur too. The takeaway was correct clearances all around, balance, and coolant testing and maintenance as a religion. We were shown liners with million plus miles that literally looked and measured as new, and other liners with cooling issues that were cavitated terribly after only a few hundred thousand. I turned wrenches at the Chevy dealership for a few years then got into industrial maintenance. Worked at a liquid detergent plant (you’re soaking in it). Cavitation in our pumps and piping was a huge problem. We had impellers that were 10+ inches diameter that would literally erode to near nothing in months. Aeration and gassing was typically the given cause. Sorry to see your woes, but great sleuthing and sharing your experience. Maybe you’ll never know the cause for sure but it looks like you’ve loaded your shotgun for great results 😊
It would be interesting to put a transducer on the #1 injector line and use a timing light to see what the actual timing is. The old International 7.3 IDIs had those built-in to #1 injector just for that purpose.
@@GordonTurnerr Still a thing to do with the repair. I'm not a member of the hindsight committee. It's their engine, not mine. Just passionate about such things is all.
@@GordonTurnerr As the cleaning man said, the evidence was destroyed by pump shop #2. Best hope is a good offense and check things thoroughly before loading the engine up again. Losing the forensic evidence is frustrating(maddening too). With nothing else to go on but guesses, I can bet the guys will be very careful and suspicious of everything so much so that it might make for temporary insanity. Lol. The passion and care put into a build then getting swiped away by a failure is not a fun thing.
I'm not a machinist or an engine builder but rather an assembler. Ring gap's and other blueprint type procedures and new valve's with magnaflux are high on my priority list. Hope you guy's get this sorted and hope it lasts for a very long time. In farming, time is money but on a larger scale than most understand.
Is there a farm tractor dealer or a repair facility nearby? They may have a pto dyno that can verify the engine’s power and how it is operating before going in the field. Many tractors can tolerate 20-30 hp over factory as long as the cooling system is keeping up. My own farm tractor is 25% over factory (60 hp factory to 80 hp according to pto dyno) Has been that way since 1999. I have worked on a turbocharged JD 4020 that my friend purchased with a seized engine as a project to fix up and sell. The fuel pump was sent to a pump shop and they said it was turned up in every way possible which caused the seizure. After the engine was overhauled, it was ran on a pto dyno which showed 120 hp. Without the turbo hooked up, the 404 cid engine made 100 hp.
In your previous videos, I could tell that the injection pump was off. If you look at the spray pattern and how it is up out of the bowl, that is a big issue because it can spray flame at your ring land area. My 25-plus years of experience is that you never want fuel to be sprayed beyond the 38° mark. The hotrod diesel guys that run out of injector volume will crank up the injector duty cycle. They end up pushing the limits on it and torch the ring lands. That is, of course, on electronic injection, but it still applies.
If it were my ag engine I would replace the oil cooler core. It is most likely the original and has deteriation/cavitation/deposits internally that could restict flow. As you know maintaining proper flow keeps the liners/pistons as cool as they can be. I have 50 years experience on diesel engines was ASE certified for Cat, Cummins, Detroit and Navistar diesel engines until I let the certification run out. Keep up the great videos!
Good catch on the valves. Also, I've never heard of rings doing what you're describing. Sounds like a quality issue to me. Great work being meticulous and solving this mystery!
I enjoy the attitude you guys have as its refreshing to see a father and son work and thrive together....when i was growing up we used a shop here in florida that was there for 40years and were good guys as well but as the years grew new faces a some issues with those new faces customer service and quality
I run a Cummins Big Cam 4. Fuel is relatively cheap, so why not pull ALL the fuel and use a new batch of fresh so you know what you have? That's what I'd do. One less variable to deal with. Love you guys!
The cavitation pitting was especially prevalent on the Cummins engines, but all diesels can be suseptable to it. Those pits will be on the major and minor thrust portions. Coolant formulations for diesels have additives to prevent the pitting, but those additives get used up over time. Regular coolant changes help. What causes the pits? Neucleate boiling in the system. As the combustion progresses and the piston transitions from the combustion stroke to the power stroke, it slaps the liner. This causes the liner to move outward a bit. Kind of like expand in a concentrated area. This gets the coolant moving outward, gaining inertia. Then the liner wall moves back to its static position, but the inertia of the coolant causes localized low pressure areas where bubbles form. Shortly later the coolant can move back putting pressure on the bubbles that are along the liner wall, collapsing the bubbles. The coolant rushes into the area the bubble had taken up, crashing into the liner. This erodes the outside of the liner. Eventually pinholes in the liner develop letting coolant into the cylinder. I was a mechanic on automotive and heavy duty for 30+ years.
I appreciate the in-depth videos of the failure! I have a 1974 Allis Chalmers 7030. When my dad and Allis Chalmers mechanic friend rebuilt it 30 years ago they ran into a similar issue. The engine would seize up when hot. I believe they had to tear it down a couple times and ended up honing it out to prevent it from happening again.
When you get it running you should check fuel timing. There is an adapter to go on the fuel line, that puts out a pulse and you can use a standard timing gun. Mark TDC #1 on the crank and put a mark on the block where you can line it up with the timing light. At that point it's like checking timing on a 350 Chevy. Would be a good check to do to verify fuel timing and to rule out any possibility that you have a timing issues. You should also be able to then run it wide open to make sure the timing advance is also advancing fuel delivery properly
Our pulling tractor uses the same type of pump as you have on the AC. I have checked timing using an injection line transducer and a timing light, it is a good thing to do, but keep in mind it will not match the pump timing. This is because the transducer is looking for swelling in the injection line, the pump is timed with air on the pump port and at less than full load the fuel has not yet built pressure when the pump port is exposed.
A friend of mine runs an fuel injection system repair service and told about the cleaning guys experience with his allis chalmers and he said the pump timing very important on the fuel system. He told me 1 degrees to a diesel is the same as 10 degrees on a gas and it would cause galling in a diesel engine.
Don't usually like very long videos, but these 23 minutes just flew! It was so interesting and so very well made!😃 Hope you find the final solution to this issue. 👍🏻 Keep up the great work, Cheers from Italy!!
Hi guys I believe you guys are looking in the right direction, I don't if you have done this yet ,but run that injection pump serial number and calibration number with the serial number of the machine.
Mentioned in the last video what your liner protrusion looked like. Doesn’t look like your too concerned about it. If you had coolant under the valve cover seems like it may have been part of the problem.
Since the injector spray pattern looked "suspicious" before it would be interesting to take a look with a borescope to see how the pattern looks with the new fuel pump rebuild.
I think this is my third time watching this series and I had the same thought. Hopefully I can catch another premiere and bring it up where they are more likely to see it.
I have had 2 engines in the machine shop recently and I wish I had been able to watch these videos years ago because bad things happened that could have been prevented had I known more about what goes on in a machine shop. Thank you for some very enjoyable videos.
@@mikeznel6048 The biggest problem is communication. I am rebuilding VW motors from the 1950s and the machine shop spends most of its time on BIG diesels. I've seen pots 6" in diameter. So I'm not asking the right questions and they are not asking the right questions so there are returns that shouldn't happen. Your channel helps me to ask the right questions.
I guess when it comes to kits ALWAYS check the specs as your experience with the ring gap shows. Like some others have pointed out before, mushroomed head tools can have metal fly off like shrapnel. Cat has a good safety video showing this called, "Shake Hands With Danger".
if i would have a gess, what happened was the pump timing being off and the 20% in fuel increase was the problem. fuel was spraying at the top/ down stroke with more fuel and the lack of proper cooling to the back cased the failure.
That little yellow flat bed ford is just awesome! I had a ford courier in my front yard for probably 2 years and sold it to a guy as a resto project. Such awesome little trucks
It may sound crazy but it sounds a bit like you had gasoline in the diesel fuel. A lot if what you experienced is textbook for that issue. You were correct to retest your fuel just to be sure it’s not loaded.
Very cool video. Educational and informative. Wish more people were that concerned about finding the root cause and not just putting a bandaid on it and calling it fixed.
Previous owner added a bit of petrol to the diesel to aid winter starting maybe, surely if the timing was way advanced you would hear it when the engine ran
Nicely done. I think we all have missed a little detail building something once in a while. Digging in and taking an honest look makes us all better going forward. Interesting that the minimum ring gap spec just left zero room for other errors - good decision to move to the middle. Farm equipment isn't racing: it just needs to be able to run all day long.
Old british leyland tractors had wet liners Rusting pin holes cavitation water in sump We took liners out braze welded holes New seals and back togeather with no leaks and ran fine
I feel sorry for all the Chalmer’s engines out in the marketplace right now because given your alls top notch video’s, everyone will want one to work on. Best engine rebuild instructional video on UA-cam. Well done fellas.
After listening to all your rebuild issues, didn't quite get the pressure on your pump being over in the beginning or not. We set our two ten up in pressure and timing a little. As I said before I would never trust the end gaps from the factory. I would have put new rings and all new exhaust valves with the issues you had. Glad you found the cracked valve. Anxious to hear that beast run and see it pull.
Those were some good finds! If you’re using the same fuel source for other equipment and not having issues I really don’t see how it could be the issue here. Looking forward to seeing how it runs when it’s done
Had a fiat allis fd30 v8 did the identical thing. Scored liners distroyed pistons. I actully went back to the old liners and old pistons new rings no more issues
If you are still concerned about excessive vibration, there are vibration analysts that specialize in internal combustion engines. They can probably tell you if you have excessive or unusual vibration by running some tests on your engine.
Glycol in an engine can do some wild things. The cylinder sleeves have tiny flex out, when they get a pressure pules (firing) and then drop back to normal creating tiny air bubble out of solution. The bubbles are like little tiny shape charges when they collapse. Cumming did some major work of venting air out of Glycol to stop it and they added some chemical in in the glycol to help stop them from forming. It can be a nasty problem.
Late commenting on this, but based on my own experiences with juicing up a 5.9 Cummins I owned that 20% over fuel on the pump was likely your main culprit. The timing being off didn't help, but adding that much extra fuel will add lots more heat to the combustion chamber. This can be really hard to identify without a pryometer to watch the exhaust gas temps. Engine coolant typically doesn't get overheated unless the cooling system was marginal in first place. Sometimes excessive black smoke will give away overfueling since there isn't enough to let all the fuel burn, but I can see that not showing up in your case since it was firing too early so it pry got a little better fuel/air mix. Seems like one those rare perfect storm combinations of several different things coming together at the right time.
Good call opening up the ring gaps. Also doesn’t surprise me that the shop found the pump was turned way up. Think I mentioned so much on a prior video comment. I’m not an allis guy (Farmall red) but the thing to keep in mind here is you are dealing with non OE parts and you have to take every spec you read with a grain of salt particularly with mid run changes like piston cooling jets. What I’ve found in my 45 years of walking this planet is that a lot of specs are general best case specs and don’t take everything into account particularly with mid run changes. The non OE manufacturer is always going to try to make things as universal as they can to save costs.
I think I would want a minimum of .005" skirt clearance especially being that the 5.9cummins of similar bore size recommends .006 for minimum and they have oil squirters of course also a lot more power. I think it points mainly to the timing was too advanced. I believe you should time the engine with the pump scribe lines lined up when the engine is at TDC. I suspect the 25deg is already built into the pump. That is how the Roosa Masters are on The Deere engines anyway. Also Deere offers a diesel coolant good for 6 years that I have seen works very well at preventing cavitation. I have a few tractor pullers that use it and the ones that do liners look like new season after season, the guys that run straight water have holes forming after the 1st season.
When you assemble the bottom end you should assemble the rotating assembly with a liberal amount of gearshield The coolant problem can be addressed by using Evans waterless coolant, not Prestone or Dexcool. Yes the valves were burned out and the guides were shot.
As a Diesel Fuel Injection Tech, the base timing of the pump is scribed on the weight carrier. On these old Roosamater (Stanadyne) pumps that line generally does not need to be remarked. However, the weight carrier could be installed 180 degrees out and only 180. We just had a John Deere pump with this issue in today. Generally, timing errors occur when the engine is not spotted in the correct location or the marks in the pump are not aligned. Timing is limited by the advance piston travel, so unless the piston was changed you won’t get more advance than stock. Now 20% over fuel delivery is massive on a piece of equipment. That can be more than the difference between a N/A and turbocharged engine. Heat, heat and more heat.
Hi gents, if it hasn't been mentioned already and before you start it up. Just do a quick spill time of the fuel pump. I mean if it's all since been rebuilt then it will spill in time with its timing marks. I imagine you're familiar with it but is a fail-safe way of picking up obvious malfunctions like stuck advances
Wise choice on ring gap, I never trust cat piston packs. Rings are always lined up in A row. Watch your exaust port temperatures they can show you misfiring , other faults, before severe damage
I would definitely add a coolant filter for peace of mind, would coat the outside of the cylinders with an anti-cavitation wax/film and help with some of these problems. you saw cylinder cavitation issues when ford went from the 6.9l to 7.3l idi increasing the displacement but making the cylinder walls thinner in the process. Regular operating conditions of the 7.3 idi were pulling pieces of metal off of the cylinder walls and the fix was a coolant filter. all of our tractor trailers that we work on at my shop have them. The nicer coolant filter pedestals have a shut off so you can replace the filter without introducing a significant amount of air into the system and I always vacuum fill the cooling systems to make sure that there is no air trapped anywhere in the motor. Good luck on the project!
At 10:32, If the engine cools front to back, why do the coolant ports that feed the liners get smaller towards the back? That is backwards. You want the smallest opening at the coldest, highest pressure point, cylinder 1. When the water is hot at the back, you need to increase flow to get the same cooling rate. Cylinder 6 where the water would be hottest gets the least water? 6 looks half the size of 1. In addition, the ones on cylinder 1&2 are very jagged while 3&4 are pretty square. Perhaps an internal casting flaw/top of port broke away?
Binge watched this series twice.....wealth of knowledge in this repair....hoping you won't have to do this next year.... watching from Ndola Zambia 🇿🇲🇿🇲
Love to see Allis Chalmers equipment. Through the years dad had a D-21, a 190 I think it was and a 7060, as well as a WC and a WD chore tractor. Thank you for doing such good work on a nice piece of equipment.
the iconic diesel noise is usually caused by the piston slap you guys had mentioned. Newer diesels with pilot injection are not nearly as loud because the pilot injection will make the piston switch from the minor to major thrust side before dumping fuel in, The old mechanicals are loud simply because they just inject the full amount of fuel all at once making the piston slam much harder against the liner when it switches thrust sides. You cant avoid cavitation either, the piston also walks its way down the liner making it vibrate. The only thing you can do is run good coolant. The coolant will deposit a protective layer that is constantly replenished as the cavitation wears away at it.
If the injektion timing is in question, you should always check! Just take of zylinder one injection line, put a clear hose on, turn the engine a couple of times over, then slowly aproche TDC on that zylinder and watch the fuel level go up! Depended on the pump, you also can take of the check valve for that line (with external fuel tank directly on the pump inlet) and watch when it stops poring out the injection line. That's easier to see then the level going up, but dose not work on alot of distribution pumps.
The largest component of the "vibration" you spoke of is the single shot injection event that delivers a sonic wave into the coolant that eventually will erode the cylinder wall on any single shot injection systems like those used on the Navistar 7.3 which required a certain type of additive to prevent this cavitation. Newer engines like the Ford 6.7 and cummins and Dmax have multiple events that cushion these combustion events by slowing the combustion pressurization rate over multiple stages. I believe the GM Duramax was the first to incorporate this timed injected event and is why current day diesels are far quieter for the big 3 pickup truck engines.
Great to see the investigation on this engine. About the pump giving to much fuel, since it is a diesel, it is opposite to a petrol engine. When a petrol engine goes lean, not enough fuel, the combustion gets hot and knock may occur. With a diesel, it can go very lean, but it will go to hot when there is to much diesel. So the 20% to much fuel, maybe combined with a wrong injection moment, can very well be the cause of high pressures and high heat.
Impressive how much that Clean Up guy knows about engines. Brilliant work you two. Sadly I'm too far away but I'd have no hesitation hiring you guys for my rebuilding needs.
This is a great video series. A few comments: 1. Make sure to add a filter to your cooling system and make sure you check the coolant to assure you have the proper additive levels to prevent cavitation on the cylinder walls. My D360 IH engine in my 886 tractor had a hole through one of the liners at the o-ring groove which was caused by cavitation which required a rebuild (which I performed). 2. Make sure the injectors are checked for proper spray pattern and do not leak under their rated pressure. I had a "new" injector in a 3-cylinder JD diesel "Yanmar" engine leak which caused pre-ignition on that cylinder which broke the ring lands on that cylinder in just a few minutes of run time which also caused me to rebuild that engine. Always check the injectors even when new out of the box. 3, make sure the holes in the "New" head gasket for water return are correctly sized., 4. You already found this out but never assume the rings are properly end gaped as they are not. I had to file the rings on the 886 kit quite a bit to get the proper end gap. 5. When you preform the die penetrate inspection you are allowed to wipe the surface with the approved cleaner on a moistened lint free cloth so you can see the defects better. I hope the 2nd rebuild work out for you.
Many, many years ago I put several hundred hours plowing fields with an AC 210 tractor that was tuned up 15% or so. We constantly had an overheating issue no matter what what parts we replaced or how tight the fan belt was. The final solution was to move the alternator from the left to the right side of the engine using brackets from the 7000 series tractors. Night and day difference. It consistently ran at the bottom of normal range regardless of weather or load.
I know this is an old video several months old, but I know on our pick ups, Diesel pick ups, timing on our injection pumps, and the spray pattern on our injectors into the cylinders on top of the pistons will have a major effect as well for heat buildup, if the injectors are messed up Don’t have a good spray pattern with the timing on. It is way off as well as a bad spray pattern. You can melt holes in your piston called torching that can happen also. As far as lubing O-rings I’ve had real good luck with CRC dielectric Greece. I never had any issues with it you have to be real easy on it super fine film usually does the trick put it on your fingers and just work it around the seals O-rings when you put them on usually does the trick Instead of using soap or oil on O-rings that’s just me everybody’s different. Everybody has their own way of doing things. I know that for sure. Good luck on this I know they’re expensive.
Really love these videos guys 👌 I think we can all agree the injection timing is the root cause, although my theories on parts of the failure are slightly different. The cavitation erosion on the liner is caused by the liner bulging during combustion rather than the force of the piston hitting it as it rocks over TDC. This would be much more pronounced if the pump was wildly over advanced. The excess pressure in the cylinder will also cause the top ring to be pushed into the bore harder, this will knock the cross hatch off almost as quick as the ends butting. Either way, the pump is the smoking gun. Keep up the good work, can't wait to hear it run.
*_I went back to the original build video, and I noticed while your backs were turned and you were on the bench working, in the background you can see a cat throw up a really big hair ball into the engine. So, there's that._*
I do this type of machining every day in Australia and it is s fun to watch how you guys do it, so much the same and different. very fun to watch and learn from these videos.
I'm just spit balling here... but I couldn't help but notice the coolant opening that goes from the feed to the liner is larger on 1 and 2 than the others (i.e, they are a rectangle where-as 3-6 are square). It seems to me that even if the entire system is being put under pressure by the pump, in other words the pump volume exceeds all the openings... 1 and 2 would get more flow no matter what... and that much being further away 5 and 6 would get less. Maybe enlarge 5 and 6?
Nothing beats engine forensics, even though I'm a retired Boilermaker/ Engineering type guy and rebuilt a few Diesels and Petrol motors over the years your never to old to learn. I have never considered liner or block cavitation due to vibration, electrolysis absolutely but cavitation only when it comes to pumps and such. But now I have a question, does increased water pressure reduce cavitation? Well apparently it does reduce cavitation. So to me logic states that a less viscous and increased pressure coolant/inhibitor possibly could reduce cavitation effects on the liners. Only if you think your liner o rings went in ok I don't know your rad cap pressure but I believe you could run it up to 14psi. Anyway don't take my word on it, but it's something to think about!
Have you considered maybe the water pump impeller is slipping or not pumping at all. Also, is it possible that belt direction is wrong and the water pump has is pumping backwards. I’m sure an old engine wouldn’t have a serpentine belt however long belts can sometimes confusing to get right. Just some thoughts.
The exhaust valves having cracks to me conferms that the timing was to advanced. 20% more fuel is nothing they can easylie handle that but i run a pyro so i know when to back off. As long as there is no gas in the diesel than any other contaminants in the fuel wont hurt it. Good luck, it looks like it should work now
the fact that the diesel injection pump was over fueling by 20 % and now been rectified if all runs ok you then want a report off the company stating the problems they found and that has been the only thing rectified thats cured your problem and ask the first pump builder what they propose to do about the inconvienance and cost its caused you
Another thing to double check is that the front pully hasn't spun causing excessive timing. They are known to spin but still run true. Double check TDC mark.
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Nice work 👏
So the cleaning guy feel comfortable with the current rebuild. Good luck
Got a bit of a question for you, I am currently fixing up a head for my Isuzu Trooper 3.1 turbo diesel engine (new valve guides, exhaust valves etc), have been cleaning up rough patches in the ports. I have noticed the valve seats protrude a ways into the ports, the portion that does protrude is rounded. Being that I am cleaning up the ports, will this be a problem for air flow?. Cheers.
Was so glad to see you take the time to make sure the alternator was in time🤣🤣🤣🤣lol
Hey, I hate to do this… The comment section mechanics and safety warriors usually drive me crazy. But this piece of advice is coming directly from a heavy equipment mechanic with direct experience on what I'm about to say lol: earlier this week I was pounding in wheel seals with my seal driver, and the head is all mushroomed over. On the third seal, I hit the driver and a chunk of that mushroom piece flew off and hit me in the face. It actually drew blood. Never had that happen before. So I see your valve seat installing tool looks just like my seal installing tool and I was thinking you might wanna grind that down a little bit so you don't end up eating a piece of that like I did lol.. nice job on the diagnostics and tear down on this. Really interesting issue that came up with this engine. I like how thorough you guys are.
I've been bit by chisels that look like that too. 3 minutes on a bench grinder every couple if years is way better than stitches.
I was taught to grind off mushrooming heads back in HS metals shop and have religiously attended to any tool began to mushroom takes less than 10 seconds
Weird the things that stick with you
@@bigj231 Sure is! I've had pieces of punches and chisels hit me in the face as well. Never pleasant! Thankfully, I've become a little bit smarter over the years. I've started wearing safety glasses & face shields much more often, when I know I'll be striking on things up close.
Other things to be very cautious around are grinding wheels and cut off wheels. I have a small piece of a 4.5"dia fiberglass cut off wheel stuck in my cheek to this very day.
It's crazy, because I can still remember it like yesterday, and it was easily a decade ago now. I remember the stinging pain, and thinking that I was glad I had safety glasses & my N95 dust mask on. I remember going to the bathroom to look in the mirror, once I had realized I was bleeding. Washed the blood off my face, put a little bit of Neosporin & a Band-Aid on it, and went back to work. Never thought about it again, as I never realized that something was actually still stuck in my cheek, at the point of the wound.
I was reconstructing & fabricating a 53' van trailer's 5th wheel pin & plate crossmembers & flooring structure. A ton of cutting, grinding, & welding going on.
Anyhow, I never knew there was a piece of grinding wheel still lodged in my face until the ER doctors did a full body scan of me, after I was in a severe pickup truck accident.
The doctors were baffled by what the strange white spot was in my cheek, in their scan picture of my skull & face.
Upon discussion, they even physically re-inspected my teeth & face. We then continued to discuss, until they concluded that what had happened to me years prior was the most likely cause of the unknown spot. LOL, so crazy!
They said that if it doesn't bother me, best to just leave it alone. Any additional intrusions at this point could just scar up and potentially cause unwanted problems to my face.
Point is, safety precautions sure can be a royal PITA sometimes, but the injuries they can prevent sure do make their use worthwhile.
@@ShaunHensley That's that I do too, grind off the mushroomed heads.
I've been noticing that as well and debated if I wanted to say something about it. 😆
Base engine Engineer from Cummins here, the connecting rod oil drilling feeding the small end was eliminated as it turns out it actually doesn't feed the small end with oil. The movement of the rod and alignment of the oil drillings ends up being such that the hole fills up with oil, but doesn't end up delivering a flow of oil to the bushing.
The rotation of the connecting rod is to move that slot away from the loaded zone of the bearing during rotation. The slot takes away from effective bearing area, and increases wear of the bearing, so while not critical, it's very beneficial to have them rotated the correct orientation.
Nice build! Really enjoy the videos!
Hope this makes it up higher in the comments
I appreciate your style and delivery. I am not a mechanic, but 67 years of farm and trucking experience, I found this episode very informative, in particular the discussion of cavitation of the cylinder walls. Your on-screen presence conveys a trust-worthy, calm, steady manner - not a fast-paced state-fair huckster selling ginsu knives. You both convey believability, and welcoming discussion about the topic at hand - in other words a couple of guys we would love to lean against the workbench and hoist a beverage or two with on a late afternoon. Cheers!
Ditto
I came here to say the same thing. This series of videos has really taught me a lot. Thanks for taking the time to put it all together.
Perfectly stated! I also appreciate their father/son relationship. I didn’t enjoy such a relationship with my father but I used that experience to make sure my two sons don’t grow up the same way as I did.
Absolutely spot on Sir.
Overfueling will increase chamber pressure, combined with the undefined fuel timing issue, I think you're still on to the solution. Nice video!
I love this channel - I feel like I'm in the shop as they have their very folksy discussion, giving clear explanations and shots of what (and how) they found while sharing their insightful conclusions. Both men are so humble as they talk about the task at hand and the pros and cons of what viewers wrote. Nicholas found the way to keep me from forwarding through the promotion by showing he and Jim continuing work on the project while pitching the sponsor. Excellent job ... thank you for sharing with us!
Don't you just love a good mechanical mystery series? It's like a game of Clue. Was it the butler with bad fuel, was it injection pump not to specifications. Or was it made in China, China?
As a fellow engine builder and diagnostition, I absolutely love your mission and style of delivery. Keep up the great content!! We never quit learning.....
I bet that pump being 20% over was the biggest cause of the problem. Because Allison had to see a problem with it for them to add piston coolers in the later model that were only slightly high Horsepower tractors. That's just my theory.
yep more fuel will make the exhaust temps shoot up
I would expect that if over fueling by the pump were the problem it would have been present in all the cylinders, not just a few with the other, good pistons looking perfect.
...and smoke like a locomotive
@@Mr_Meowingtons to a point, then smoke bad
@@Mr_Meowingtons to a point, then bad smoke!!
Have you guys thought about running an EGT probe and gauge to help keep an eye on the engine? I would think it would be a worth while investment considering all the issues you've had and work you've put into this tractor.
I love watching father and son do stuff together, that is awesome.
It really misses my dad. I hope he's having a good time and heaven.
This is one of the main things I miss. I am doing stuff like this with my father. Hold on to it. It will be the best memories when he's not there.
I work for an engine MRO shop. I’m really impressed to see what you guys are doing just the two of you. Keep up the good work!
I'm gonna SWAG an idea. Add a braided ground strap from the block to chassis ground...make sure it's not bolted over paint! Also, was the oil cooler clear for coolant flow?
What a fantastic video guys. I could listen to your dad and you as well, explain things all day. I still say he should be a teacher, there's not many good ones left.
The cam ring in the pump was flipped. Shame it was missed when it was torn apart but I guarantee that’s why it was 180* out. If the new shop built the pump right this time it should be fine even with 20% more fuel.
Pretty sure that pump wasn't a true 180 degree off. Pump shop screwed up big time
Injecting fuel too early will overheat pistons just as preignition (over advanced spark) will damage a gasoline engine.
Injecting too much fuel into a diesel just makes it run faster.
@@Dave5843-d9m no…
That valve being pushed up like that is called tuliping. Steve Morris had an engine that had this issue a while ago.
Great explanation of what you guys have seen from the autopsy from Allis.
Joe
Well done on a very good failure analysis. Think your fuel pump build is definitely your cause. Might be a good idea to spill time the pump when fitting it and volume check the injectors before fitting them
Agreed, I am interested in hearing more about how the injectors check out.
Liquid dye penetrant. This is Type 2, method C, form D.
Always pre-clean the part you're going to inspect with the solvent that comes in the kit.
Allow it to dry for about 20 minutes.
Spray the penetrant on the area of interest and let it dwell for 10 minutes minimum.
Wipe off the excess using a lint free cloth to remove the bulk penetrant, followed by a solvent dampened lint free cloth. Never spray solvent on the part to remove the excess penetrant or you will remove the penetrant from the defect and ruin you ability to detect it.
Let the solvent evaporate for 10 minutes.
Apply the non-aqueous developer by spraying in short bursts to just mist the part. Do not overapply the developer. Let it dwell for 10 minutes minimum and evaluate.
Pre-cleaning removes the organic material (oil, grease, etc). This will allow the penetrant to fill the crack.
A better inspection method is magnetic particle inspection. This method only works on ferrous materials. Cleaning is not as important.
I gather you have done penetrant inspection a few times before! Are you working in Aerospace NDT?
Suggestion - when you start the engine check the manifold exhaust temperature with a pyrometer or heat gun for over-fuelling - especially under load, also
Have you checked that you have the correct nozzles in the injectors and that they are set to the correct pressures / spray pattern?
Exactly
Yes,nozzles hole angle
If only UA-cam had this quality of content throughout, how awesome would that be! Well done guys, & good luck going forward.
I would recommend installing a pyrometer to monitor exhaust temps?
Since I didn’t hear you mention it, are you using coolant with DCA or SCA additives for Diesel engines?
It probably wouldn’t have prevented the liner putting in your case, it is necessary for long term.
Just my 2 cents, for what it’s worth.
Keep up the good work, I really enjoy your vids.
You guys are super-methodical and careful, analysing everything and considering things from all conceivable angles. Bravo!
Maybe I missed you talking about it, but have you run the injectors on a test stand? The pump may have been turned up some but that wouldn't have been as big an issue as if an injector was over fueling.
When I was at UNOH for auto/diesel in ‘82/3. We talked a lot about the prevalence of cavitation in diesel’s. The explanation we were taught was also mechanical vibration as a primary cause but also coolant quality and chemistry. Aeration is a common factor. A comment mentioning grounding straps seems good advice also as cathodic corrosion can occur too. The takeaway was correct clearances all around, balance, and coolant testing and maintenance as a religion. We were shown liners with million plus miles that literally looked and measured as new, and other liners with cooling issues that were cavitated terribly after only a few hundred thousand.
I turned wrenches at the Chevy dealership for a few years then got into industrial maintenance. Worked at a liquid detergent plant (you’re soaking in it). Cavitation in our pumps and piping was a huge problem. We had impellers that were 10+ inches diameter that would literally erode to near nothing in months. Aeration and gassing was typically the given cause. Sorry to see your woes, but great sleuthing and sharing your experience. Maybe you’ll never know the cause for sure but it looks like you’ve loaded your shotgun for great results 😊
It would be interesting to put a transducer on the #1 injector line and use a timing light to see what the actual timing is. The old International 7.3 IDIs had those built-in to #1 injector just for that purpose.
This sounds like a great idea! Just to have an extra piece of mind. And check injection is happening when it supposed to.
In hindsight that would've been a great idea!👍
@@GordonTurnerr Still a thing to do with the repair. I'm not a member of the hindsight committee. It's their engine, not mine. Just passionate about such things is all.
@@nhzxboi yeah for sure, but it would've been nice to possibly find that smoking gun ☺
@@GordonTurnerr As the cleaning man said, the evidence was destroyed by pump shop #2. Best hope is a good offense and check things thoroughly before loading the engine up again. Losing the forensic evidence is frustrating(maddening too). With nothing else to go on but guesses, I can bet the guys will be very careful and suspicious of everything so much so that it might make for temporary insanity. Lol. The passion and care put into a build then getting swiped away by a failure is not a fun thing.
I'm not a machinist or an engine builder but rather an assembler. Ring gap's and other blueprint type procedures and new valve's with magnaflux are high on my priority list. Hope you guy's get this sorted and hope it lasts for a very long time. In farming, time is money but on a larger scale than most understand.
Is there a farm tractor dealer or a repair facility nearby? They may have a pto dyno that can verify the engine’s power and how it is operating before going in the field.
Many tractors can tolerate 20-30 hp over factory as long as the cooling system is keeping up.
My own farm tractor is 25% over factory (60 hp factory to 80 hp according to pto dyno) Has been that way since 1999.
I have worked on a turbocharged JD 4020 that my friend purchased with a seized engine as a project to fix up and sell.
The fuel pump was sent to a pump shop and they said it was turned up in every way possible which caused the seizure.
After the engine was overhauled, it was ran on a pto dyno which showed 120 hp. Without the turbo hooked up, the 404 cid engine made 100 hp.
In your previous videos, I could tell that the injection pump was off. If you look at the spray pattern and how it is up out of the bowl, that is a big issue because it can spray flame at your ring land area. My 25-plus years of experience is that you never want fuel to be sprayed beyond the 38° mark. The hotrod diesel guys that run out of injector volume will crank up the injector duty cycle. They end up pushing the limits on it and torch the ring lands. That is, of course, on electronic injection, but it still applies.
If it were my ag engine I would replace the oil cooler core. It is most likely the original and has deteriation/cavitation/deposits internally that could restict flow. As you know maintaining proper flow keeps the liners/pistons as cool as they can be. I have 50 years experience on diesel engines was ASE certified for Cat, Cummins, Detroit and Navistar diesel engines until I let the certification run out. Keep up the great videos!
Make sure to use a charged cooland to prevent cavitation and electrolysis NAPA has a purple one that I use in my 77 AC 7040...
What did the injection pump folks think was the issue? Monitoring EGTs should give you a good indication of what is going on up top.
Good catch on the valves. Also, I've never heard of rings doing what you're describing. Sounds like a quality issue to me. Great work being meticulous and solving this mystery!
I enjoy the attitude you guys have as its refreshing to see a father and son work and thrive together....when i was growing up we used a shop here in florida that was there for 40years and were good guys as well but as the years grew new faces a some issues with those new faces customer service and quality
Just a note Valve rotators go on the intake, on an Allis Chalmers
I run a Cummins Big Cam 4. Fuel is relatively cheap, so why not pull ALL the fuel and use a new batch of fresh so you know what you have? That's what I'd do. One less variable to deal with. Love you guys!
The cavitation pitting was especially prevalent on the Cummins engines, but all diesels can be suseptable to it. Those pits will be on the major and minor thrust portions. Coolant formulations for diesels have additives to prevent the pitting, but those additives get used up over time. Regular coolant changes help.
What causes the pits? Neucleate boiling in the system. As the combustion progresses and the piston transitions from the combustion stroke to the power stroke, it slaps the liner. This causes the liner to move outward a bit. Kind of like expand in a concentrated area. This gets the coolant moving outward, gaining inertia. Then the liner wall moves back to its static position, but the inertia of the coolant causes localized low pressure areas where bubbles form. Shortly later the coolant can move back putting pressure on the bubbles that are along the liner wall, collapsing the bubbles. The coolant rushes into the area the bubble had taken up, crashing into the liner. This erodes the outside of the liner. Eventually pinholes in the liner develop letting coolant into the cylinder.
I was a mechanic on automotive and heavy duty for 30+ years.
I appreciate the in-depth videos of the failure! I have a 1974 Allis Chalmers 7030. When my dad and Allis Chalmers mechanic friend rebuilt it 30 years ago they ran into a similar issue. The engine would seize up when hot. I believe they had to tear it down a couple times and ended up honing it out to prevent it from happening again.
I'm starting to develop an emotional connection to this tractor. Very up and down.
It’s a love hate relationship
When you get it running you should check fuel timing. There is an adapter to go on the fuel line, that puts out a pulse and you can use a standard timing gun. Mark TDC #1 on the crank and put a mark on the block where you can line it up with the timing light. At that point it's like checking timing on a 350 Chevy. Would be a good check to do to verify fuel timing and to rule out any possibility that you have a timing issues. You should also be able to then run it wide open to make sure the timing advance is also advancing fuel delivery properly
Our pulling tractor uses the same type of pump as you have on the AC. I have checked timing using an injection line transducer and a timing light, it is a good thing to do, but keep in mind it will not match the pump timing. This is because the transducer is looking for swelling in the injection line, the pump is timed with air on the pump port and at less than full load the fuel has not yet built pressure when the pump port is exposed.
A friend of mine runs an fuel injection system repair service and told about the cleaning guys experience with his allis chalmers and he said the pump timing very important on the fuel system. He told me 1 degrees to a diesel is the same as 10 degrees on a gas and it would cause galling in a diesel engine.
THE HARMONIC BALANCER SLIPPED. SHOWING TIMING TO BE WRONG. I have to many times. RICK ROBERTS.
Don't usually like very long videos, but these 23 minutes just flew! It was so interesting and so very well made!😃 Hope you find the final solution to this issue. 👍🏻 Keep up the great work, Cheers from Italy!!
As a 'Diesel Fitter', I am learning SO much from watching this channel. Love your work, gentlemen! Keep it up!!👍🙂
Hi guys I believe you guys are looking in the right direction, I don't if you have done this yet ,but run that injection pump serial number and calibration number with the serial number of the machine.
Mentioned in the last video what your liner protrusion looked like. Doesn’t look like your too concerned about it. If you had coolant under the valve cover seems like it may have been part of the problem.
i love at 18:00 Jim basically saying "I'll do it after you leave"
You guys are great to watch
Since the injector spray pattern looked "suspicious" before it would be interesting to take a look with a borescope to see how the pattern looks with the new fuel pump rebuild.
I think this is my third time watching this series and I had the same thought. Hopefully I can catch another premiere and bring it up where they are more likely to see it.
I have had 2 engines in the machine shop recently and I wish I had been able to watch these videos years ago because bad things happened that could have been prevented had I known more about what goes on in a machine shop. Thank you for some very enjoyable videos.
These videos barely scratch the surface.
@@mikeznel6048 The biggest problem is communication. I am rebuilding VW motors from the 1950s and the machine shop spends most of its time on BIG diesels. I've seen pots 6" in diameter. So I'm not asking the right questions and they are not asking the right questions so there are returns that shouldn't happen. Your channel helps me to ask the right questions.
I guess when it comes to kits ALWAYS check the specs as your experience with the ring gap shows. Like some others have pointed out before, mushroomed head tools can have metal fly off like shrapnel. Cat has a good safety video showing this called, "Shake Hands With Danger".
if i would have a gess, what happened was the pump timing being off and the 20% in fuel increase was the problem. fuel was spraying at the top/ down stroke with more fuel and the lack of proper cooling to the back cased the failure.
That little yellow flat bed ford is just awesome! I had a ford courier in my front yard for probably 2 years and sold it to a guy as a resto project. Such awesome little trucks
It may sound crazy but it sounds a bit like you had gasoline in the diesel fuel. A lot if what you experienced is textbook for that issue. You were correct to retest your fuel just to be sure it’s not loaded.
Very cool video. Educational and informative. Wish more people were that concerned about finding the root cause and not just putting a bandaid on it and calling it fixed.
Previous owner added a bit of petrol to the diesel to aid winter starting maybe, surely if the timing was way advanced you would hear it when the engine ran
Nicely done. I think we all have missed a little detail building something once in a while. Digging in and taking an honest look makes us all better going forward. Interesting that the minimum ring gap spec just left zero room for other errors - good decision to move to the middle. Farm equipment isn't racing: it just needs to be able to run all day long.
Old british leyland tractors had wet liners
Rusting pin holes cavitation water in sump
We took liners out braze welded holes
New seals and back togeather with no leaks and ran fine
I feel sorry for all the Chalmer’s engines out in the marketplace right now because given your alls top notch video’s, everyone will want one to work on. Best engine rebuild instructional video on UA-cam. Well done fellas.
You could add 2 pyrometers to the exhaust front and rear to measure the temp and see if you are getting to hot when pulling
I'm excited to see it going back together. I hope it goes well. It seems like you've covered all your bases.
After listening to all your rebuild issues, didn't quite get the pressure on your pump being over in the beginning or not. We set our two ten up in pressure and timing a little. As I said before I would never trust the end gaps from the factory. I would have put new rings and all new exhaust valves with the issues you had. Glad you found the cracked valve.
Anxious to hear that beast run and see it pull.
Those were some good finds! If you’re using the same fuel source for other equipment and not having issues I really don’t see how it could be the issue here. Looking forward to seeing how it runs when it’s done
Awesome video! Thanks for taking us down the rabbit hole and explaining every aspect of processes applied for your diagnosis and repair of the Old AC.
I appreciate the fact you guys are going through the trouble shooting and thought process. Even though the engine blew up, and you could hide it.
Had a fiat allis fd30 v8 did the identical thing. Scored liners distroyed pistons. I actully went back to the old liners and old pistons new rings no more issues
If you are still concerned about excessive vibration, there are vibration analysts that specialize in internal combustion engines. They can probably tell you if you have excessive or unusual vibration by running some tests on your engine.
Glycol in an engine can do some wild things. The cylinder sleeves have tiny flex out, when they get a pressure pules (firing) and then drop back to normal creating tiny air bubble out of solution. The bubbles are like little tiny shape charges when they collapse. Cumming did some major work of venting air out of Glycol to stop it and they added some chemical in in the glycol to help stop them from forming. It can be a nasty problem.
Late commenting on this, but based on my own experiences with juicing up a 5.9 Cummins I owned that 20% over fuel on the pump was likely your main culprit. The timing being off didn't help, but adding that much extra fuel will add lots more heat to the combustion chamber. This can be really hard to identify without a pryometer to watch the exhaust gas temps. Engine coolant typically doesn't get overheated unless the cooling system was marginal in first place. Sometimes excessive black smoke will give away overfueling since there isn't enough to let all the fuel burn, but I can see that not showing up in your case since it was firing too early so it pry got a little better fuel/air mix. Seems like one those rare perfect storm combinations of several different things coming together at the right time.
Good call opening up the ring gaps. Also doesn’t surprise me that the shop found the pump was turned way up. Think I mentioned so much on a prior video comment. I’m not an allis guy (Farmall red) but the thing to keep in mind here is you are dealing with non OE parts and you have to take every spec you read with a grain of salt particularly with mid run changes like piston cooling jets. What I’ve found in my 45 years of walking this planet is that a lot of specs are general best case specs and don’t take everything into account particularly with mid run changes. The non OE manufacturer is always going to try to make things as universal as they can to save costs.
I think I would want a minimum of .005" skirt clearance especially being that the 5.9cummins of similar bore size recommends .006 for minimum and they have oil squirters of course also a lot more power. I think it points mainly to the timing was too advanced. I believe you should time the engine with the pump scribe lines lined up when the engine is at TDC. I suspect the 25deg is already built into the pump. That is how the Roosa Masters are on The Deere engines anyway. Also Deere offers a diesel coolant good for 6 years that I have seen works very well at preventing cavitation. I have a few tractor pullers that use it and the ones that do liners look like new season after season, the guys that run straight water have holes forming after the 1st season.
Like your Mazda B1600 brings back some memories of when I drove 1 in the late 70's
When you assemble the bottom end you should assemble the rotating assembly with a liberal amount of gearshield
The coolant problem can be addressed by using Evans waterless coolant, not Prestone or Dexcool.
Yes the valves were burned out and the guides were shot.
As a Diesel Fuel Injection Tech, the base timing of the pump is scribed on the weight carrier. On these old Roosamater (Stanadyne) pumps that line generally does not need to be remarked. However, the weight carrier could be installed 180 degrees out and only 180. We just had a John Deere pump with this issue in today. Generally, timing errors occur when the engine is not spotted in the correct location or the marks in the pump are not aligned. Timing is limited by the advance piston travel, so unless the piston was changed you won’t get more advance than stock. Now 20% over fuel delivery is massive on a piece of equipment. That can be more than the difference between a N/A and turbocharged engine. Heat, heat and more heat.
Hi gents, if it hasn't been mentioned already and before you start it up. Just do a quick spill time of the fuel pump. I mean if it's all since been rebuilt then it will spill in time with its timing marks.
I imagine you're familiar with it but is a fail-safe way of picking up obvious malfunctions like stuck advances
Wise choice on ring gap, I never trust cat piston packs. Rings are always lined up in A row. Watch your exaust port temperatures they can show you misfiring , other faults, before severe damage
I would definitely add a coolant filter for peace of mind, would coat the outside of the cylinders with an anti-cavitation wax/film and help with some of these problems. you saw cylinder cavitation issues when ford went from the 6.9l to 7.3l idi increasing the displacement but making the cylinder walls thinner in the process. Regular operating conditions of the 7.3 idi were pulling pieces of metal off of the cylinder walls and the fix was a coolant filter. all of our tractor trailers that we work on at my shop have them. The nicer coolant filter pedestals have a shut off so you can replace the filter without introducing a significant amount of air into the system and I always vacuum fill the cooling systems to make sure that there is no air trapped anywhere in the motor. Good luck on the project!
At 10:32, If the engine cools front to back, why do the coolant ports that feed the liners get smaller towards the back? That is backwards. You want the smallest opening at the coldest, highest pressure point, cylinder 1. When the water is hot at the back, you need to increase flow to get the same cooling rate. Cylinder 6 where the water would be hottest gets the least water? 6 looks half the size of 1. In addition, the ones on cylinder 1&2 are very jagged while 3&4 are pretty square. Perhaps an internal casting flaw/top of port broke away?
Always check ring gap. You did right going between specs they're thin and expand quite a bit when they heat up.
Binge watched this series twice.....wealth of knowledge in this repair....hoping you won't have to do this next year.... watching from Ndola Zambia 🇿🇲🇿🇲
Love to see Allis Chalmers equipment. Through the years dad had a D-21, a 190 I think it was and a 7060, as well as a WC and a WD chore tractor. Thank you for doing such good work on a nice piece of equipment.
the iconic diesel noise is usually caused by the piston slap you guys had mentioned. Newer diesels with pilot injection are not nearly as loud because the pilot injection will make the piston switch from the minor to major thrust side before dumping fuel in, The old mechanicals are loud simply because they just inject the full amount of fuel all at once making the piston slam much harder against the liner when it switches thrust sides. You cant avoid cavitation either, the piston also walks its way down the liner making it vibrate. The only thing you can do is run good coolant. The coolant will deposit a protective layer that is constantly replenished as the cavitation wears away at it.
If the injektion timing is in question, you should always check!
Just take of zylinder one injection line, put a clear hose on, turn the engine a couple of times over, then slowly aproche TDC on that zylinder and watch the fuel level go up! Depended on the pump, you also can take of the check valve for that line (with external fuel tank directly on the pump inlet) and watch when it stops poring out the injection line. That's easier to see then the level going up, but dose not work on alot of distribution pumps.
The largest component of the "vibration" you spoke of is the single shot injection event that delivers a sonic wave into the coolant that eventually will erode the cylinder wall on any single shot injection systems like those used on the Navistar 7.3 which required a certain type of additive to prevent this cavitation. Newer engines like the Ford 6.7 and cummins and Dmax have multiple events that cushion these combustion events by slowing the combustion pressurization rate over multiple stages. I believe the GM Duramax was the first to incorporate this timed injected event and is why current day diesels are far quieter for the big 3 pickup truck engines.
Great to see the investigation on this engine. About the pump giving to much fuel, since it is a diesel, it is opposite to a petrol engine. When a petrol engine goes lean, not enough fuel, the combustion gets hot and knock may occur. With a diesel, it can go very lean, but it will go to hot when there is to much diesel. So the 20% to much fuel, maybe combined with a wrong injection moment, can very well be the cause of high pressures and high heat.
Impressive how much that Clean Up guy knows about engines.
Brilliant work you two.
Sadly I'm too far away but I'd have no hesitation hiring you guys for my rebuilding needs.
Great job Fellas. What a blessing you have your father to work with. 👍🏼🙏🏼
This is a great video series. A few comments: 1. Make sure to add a filter to your cooling system and make sure you check the coolant to assure you have the proper additive levels to prevent cavitation on the cylinder walls. My D360 IH engine in my 886 tractor had a hole through one of the liners at the o-ring groove which was caused by cavitation which required a rebuild (which I performed). 2. Make sure the injectors are checked for proper spray pattern and do not leak under their rated pressure. I had a "new" injector in a 3-cylinder JD diesel "Yanmar" engine leak which caused pre-ignition on that cylinder which broke the ring lands on that cylinder in just a few minutes of run time which also caused me to rebuild that engine. Always check the injectors even when new out of the box. 3, make sure the holes in the "New" head gasket for water return are correctly sized., 4. You already found this out but never assume the rings are properly end gaped as they are not. I had to file the rings on the 886 kit quite a bit to get the proper end gap. 5. When you preform the die penetrate inspection you are allowed to wipe the surface with the approved cleaner on a moistened lint free cloth so you can see the defects better. I hope the 2nd rebuild work out for you.
Many, many years ago I put several hundred hours plowing fields with an AC 210 tractor that was tuned up 15% or so. We constantly had an overheating issue no matter what what parts we replaced or how tight the fan belt was. The final solution was to move the alternator from the left to the right side of the engine using brackets from the 7000 series tractors. Night and day difference. It consistently ran at the bottom of normal range regardless of weather or load.
I know this is an old video several months old, but I know on our pick ups, Diesel pick ups, timing on our injection pumps, and the spray pattern on our injectors into the cylinders on top of the pistons will have a major effect as well for heat buildup, if the injectors are messed up Don’t have a good spray pattern with the timing on. It is way off as well as a bad spray pattern. You can melt holes in your piston called torching that can happen also. As far as lubing O-rings I’ve had real good luck with CRC dielectric Greece. I never had any issues with it you have to be real easy on it super fine film usually does the trick put it on your fingers and just work it around the seals O-rings when you put them on usually does the trick Instead of using soap or oil on O-rings that’s just me everybody’s different. Everybody has their own way of doing things. I know that for sure. Good luck on this I know they’re expensive.
i've seen 6.7 ford valves cracked like that a lot lately. High cyl temp and combustion pressure makes a lot of sense.
Really love these videos guys 👌 I think we can all agree the injection timing is the root cause, although my theories on parts of the failure are slightly different. The cavitation erosion on the liner is caused by the liner bulging during combustion rather than the force of the piston hitting it as it rocks over TDC. This would be much more pronounced if the pump was wildly over advanced. The excess pressure in the cylinder will also cause the top ring to be pushed into the bore harder, this will knock the cross hatch off almost as quick as the ends butting. Either way, the pump is the smoking gun. Keep up the good work, can't wait to hear it run.
I was lapping the valves on my Atomic 4 flathead marine engine when one just fell OFF the stem I was quite happy it happened in the shop
*_I went back to the original build video, and I noticed while your backs were turned and you were on the bench working, in the background you can see a cat throw up a really big hair ball into the engine. So, there's that._*
I do this type of machining every day in Australia and it is s fun to watch how you guys do it, so much the same and different. very fun to watch and learn from these videos.
I'm just spit balling here... but I couldn't help but notice the coolant opening that goes from the feed to the liner is larger on 1 and 2 than the others (i.e, they are a rectangle where-as 3-6 are square). It seems to me that even if the entire system is being put under pressure by the pump, in other words the pump volume exceeds all the openings... 1 and 2 would get more flow no matter what... and that much being further away 5 and 6 would get less. Maybe enlarge 5 and 6?
Nothing beats engine forensics, even though I'm a retired Boilermaker/ Engineering type guy and rebuilt a few Diesels and Petrol motors over the years your never to old to learn. I have never considered liner or block cavitation due to vibration, electrolysis absolutely but cavitation only when it comes to pumps and such. But now I have a question, does increased water pressure reduce cavitation? Well apparently it does reduce cavitation. So to me logic states that a less viscous and increased pressure coolant/inhibitor possibly could reduce cavitation effects on the liners. Only if you think your liner o rings went in ok I don't know your rad cap pressure but I believe you could run it up to 14psi. Anyway don't take my word on it, but it's something to think about!
Have you considered maybe the water pump impeller is slipping or not pumping at all. Also, is it possible that belt direction is wrong and the water pump has is pumping backwards. I’m sure an old engine wouldn’t have a serpentine belt however long belts can sometimes confusing to get right. Just some thoughts.
You need to put 6 egt probes in so you can watch things. I know it's would be expensive but worth it
The exhaust valves having cracks to me conferms that the timing was to advanced. 20% more fuel is nothing they can easylie handle that but i run a pyro so i know when to back off. As long as there is no gas in the diesel than any other contaminants in the fuel wont hurt it. Good luck, it looks like it should work now
the fact that the diesel injection pump was over fueling by 20 % and now been rectified if all runs ok you then want a report off the company stating the problems they found and that has been the only thing rectified thats cured your problem and ask the first pump builder what they propose to do about the inconvienance and cost its caused you
Another thing to double check is that the front pully hasn't spun causing excessive timing. They are known to spin but still run true. Double check TDC mark.
Really like the detective work. Brings home the lessons and instructions about tolerance and double checking work.