So You've Got A Blown Head Gasket - Here's What You Need To Know To Make It Right
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- Опубліковано 24 лис 2024
- In our last video we gave this 4.0 Jeep engine a compression test, and determined that the gasket between cylinder's 3 and 4 had blown out.
Now, with the head pulled, we can see the obvious damage, but it takes some mechanical detective work to figure out why it happened in the first place.
Here's what we found, what we determined and the steps we're taking to make sure it doesn't happen again.
#cars #engine #autorepair #diy
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That was a Friday afternoon at the factory head and the guy could already taste his first beer.
Or he was an alcoholic and had a bottle stashed somewhere that he drank all day long.
You must have read the book "Wheels", explaining why you wanted a car built on a Tuesday, Wednesday, or a Thursday!
@@carlc5748Yup, reduced fudge factor minimizing slacker risk, which leaves one more possibility of "c'mon Rudy, let's get to the cafe lunch special before it's over!"
@@carlc5748 no I just worked in a factory for 6 years. You don’t want a Friday machine!
Could have been a Monday after a bender😂
Somebody has been in there before you, i have never seen factory machine work that bad.
Nicely done Tony. Back to the UTG of old, simple explanations for the newbies at this kind of thing. 👍
The mill or decking machine had a worn saddle that holds the work surface or table. It's rocking as it passes center, so the tool is back cutting.
Great observation. Experience.
Thanks for confirming that possible failure mode. I had noticed the back cutting and it was obvious that something was far out of alignment with the tooling but I hadn't figured a reason behind it yet. I don't do engines in my machine shop but seeing that finish from a fly cutter would have had me shutting down and chasing it as a major intolerable issue on my own stuff. What you mentioned would cause slight concavity which helps explain the effects being primarily centered across the block also such as those extra gaps at the central water passages.
I think the head was done with a flycutter instead of a face mill at some scam shop.@@OldGeezerstoolbox
That head was fly cut ideally you want a cylinder head finished to between 30 and 50 ra. Some old people use to think fly cutting worked better on graphite head gaskets but that was bs, the smoother the head and block finish the better.
are you sure it was made by a mill?
I worked in a machine shop for 5 years doing nothing but cylinder heads, never seen surface like that. One thing I would strongly recommend for anyone is to use a straightedge long enough to span the entire length of the head and use feeler gauges to figure out the straightness , checking in the middle and both sides and in a x pattern, especially on a straight six.
I don't think that was the factory surfacing, the head has likely been surfaced somewhere in it's life - poorly!
Your tip about not using a "ziz-wheel" (die grinder with a "rol-loc" scotch brite disc) is a good one. I have dozens of hours of experience using one and it still gives me great concern putting one to mated surfaces because gouging is such an easy thing to do. If you know what you're doing, are pressed for time and take the care, ok but otherwise, i have a scraper handle that holds a standard razor blade and that works great with a torch, just like you said.
It's easy to want to "be like the pros" and pick up die grinders and other power tools but, they can get you into trouble just as easily as they can get you out. "Take your time" is one of the best pieces of advice you can give to a home mechanic/hobbiest. 😊
Keep doing you bud.
I'm a 'pro' (forklift mechanic) and I'll only clean heads/block decks by hand. A good head gasket job is like a good paint job - it's all in the prep 👍.
In most cases for me, the cleaning is the longest part of the job.
Yep I work at a dodge dealer and only use plastic razors on my scrappers or very carefully use a carbide scraper pulling backwards to avoid damaging aluminum heads and blocks. Too easy to screw up and if I screw something up bad enough it's coming out of my pocket. Thats the one time you should take your time on a head job professionally.
Tony,there is no way that head came from the factory like that. It’s been off before and some jackwagom machine shop screwed it up.
You’d be surprised
I agree, the 4.0 Jeep is widly known to be one of the most reliable engines ever made, and I refuse to believe Chrysler Corp would have such bad machining. if that was the norm, this would be a common problem with these engines.
Yup. 👍
@@NGG1983 I've worked on old conventional machine shop equipment and know exactly how those gouges were made. They're not from the OEM. From beatup equipment. My concern is how much did these nit wits take off the head? Is it even usable? It would dramatically effect the pushrod geometry and a few other things. Was the increased compression enough to help take out the gasket?
And Tony should have added how important it is to torque head bolts in the proper sequence. Start in the middle Always!! 🙂
I have a 89 XJ ( 4wd ) that on occasion I've used to tow a 20ft. travel trailer (5000 lbs+). With the right hitch, sway bars, and care in how you load it, has proved stable even in a moderate cross wind. But like you pointed out, a little anemic under the hood. I won't be trying to pull any 6000 ft. passes with it, though. I've also pulled my flatbed with mid sized cars on it, and it did that fairly well. Should be just fine running to the strip and back.
Still raining.....good weather to work on the Jeep!
😂It’s pouring! I agree, great time to work- if you’re inside!
the weak points in the drivetrain as a tow vehicle is the short whellbase. the rear driveshaft angle will wear out those small U joints pretty quick. The short wheel base will also cause handling issues with the rear suspension being so soft the trailer is going to push the car around.
I will confirm the stock factory springs are a bit soft and the brakes with even stock tires work but not realy impressive at least in stock form. But the brakes you can go to larger front rotor and a rotor kit for 8 1/4 rear or 8.8 rear with rotors , the rear springs can be built stiffer or helper springs but you will lose some articulation but that depends on what he intends for the jeep. Not realy sure what he intends to pull most of the time. Overall though uncle Tony can make a car pull the front wheels pretty sure he has a plan and ahead of the game on this. Realy just intrested in seeing the build.
Tony - Back in the day I had a '67 Chevy panel truck (a suburban without side glass). It came to me with a 250 straight six (one barrel carb) and a 3 speed manual. I installed a 400 turbo and hitched up a 2800 pound travel trailer and probably another 500 pounds or more of gear in the back of the truck, and hauled it around for two years while my wife and I traveled an itinerate circuit with other artisans. The only time I really questioned my mission was going up Jellico mountain in Tennessee with my foot to the floor going 45 mph. However, I figured I wasn't doing too bad at that since I was still passing many a semi rig! Made it over the mountain just fine, and never dropped below 45 mph. I think your Jeep will get you where you want to go.
I ran a couple 62's, a chevy and a GMC with a 235,and 305 v-6, I really enjoyed those, had a 58 panel with a 235 too, for a few short months.
1970s? Did you ever meet a couple out of Florida in an old Dodge A series van? They did cloisonné type stuff.
Swap that 250 out for a 292, and it would pull anything, no problem...just have to stop at the gas station a lot more often....
I had a '65 Bel Air with a 230 six and power glide. I put in a Stewart Warner mechanical temp gauge. When towing with that I ignored the speedometer, and drove according to the temp gauge. I blame the teeny tiny radiator in that case.
I am in envy, don't we wish we could have what we had back then? My neighbor had a 33 or so Packard he rolled out in the alley saturdays washed waxed for church.@@craigbenz4835
Tony,
Invest in a TRUE machinists straight edge. Yes they are pricey, but the cost is offset by the accuracy and peace of mind that what you've checked is true. Years ago I knew I would be doing head gaskets and other work requiring one. I bought a Starrett 48" machinists straight edge, accurate to 0.0002, it was about $500.
For "truing-up" heads, I got a large piece of polished granite building cladding that was a scrap piece from a commercial stone building supply house. It was about 3' X 4' and an inch thick and was damaged because a small corner was broken off of it. I think I paid about $50 for it. When I checked it with the straight edge, it was dead flat and true in all directions !
For doing heads, I lightly fog some 3M "77" spray adhesive on the granite and then, using a rubber Formica" roller to glue down sheets of 3M "Tri-m-ite" sheets of wet / dry paper to it, no over-lap, just edge to edge. I use water for aluminum heads, light oil for cast iron and lay the head on it and work in circular motions, a poor mans way of lapping. A friend of mine has an optical comparator ( owns a machine shop ) and I've gotten surfaces finer than 30 RA this way. ( RA is Roughness Average, measured in microns. millionth's of an inch.)
Needed this RA for using 6 star HG's for earlier Subaru's that were built to stage 2, notorious for HG failures. NEVER had one come back.
Automotive machine shop head grinders typically end up at about 100 RA, maybe 90 RA in a perfect world. 30 RA looks like a mirror.
GREAT wisdom on "reading" the gasket! I'll be pulling the head on a straight 6 with poor compression and will keep this in mind!
Jeep fanatic here. It's overstated I know but the 4.2 and 4 ltr are up near the top of best motors ever. Glad to see you playing with one. I've had about every jeep but an old CJ 5 with a built 4.2 grew on me. Not many sports cars would compare IMO.
I would only use a straight edge that is long enough to hang past each end of the head and the deck surface. And I would check valve guides before I would send it out . And I would do pc press on seals . Valve job ? Or just lap them . I always spend to much time and money. Lol but I don't have come backs . Have a great day sir !
I'm with Tony on leakdown tests. They can tell you a lot, but most people just need to know if they're pulling the head, or the entire engine. A basic compression test will tell you that.
I honestly thought you were gonna let it ride like that. Either the cutter was incredibly dull or the feed rate was set at light speed. I'm blown away at how gnarly that machining is.
For those who replaced everything (stock parts of course) in your cooling system but still run hot, the beginnings of this type of HG issue is your likely culprit. Mine wasn't totally blown out like this but was starting to in the middle (like cyl 2-3 and 4-5 on this one). New HG, head resurfaced and no more running hot issues.
Here comes a daily series!!!
Great! ❤
I surface a head like that myself with sandpaper. I cut open a belt sander belt, then glue it down to something flat ( a piece of glass, stone counter top, tombstone, ETC). Then I just slide the head around on the sandpaper until all the dark marks are gone. The head won't have to be disassembled, I don't have to wait on the machine shop, and it saves cash.
I do own equipment to do a valve job, so I usually do a valve job at the same time, but it isn't always necessary.
I can't believe the grooves in that head from the factory!!
I saw a video where a guy re surfaced a cylinder head using a thick piece of plate glass covered with sandpaper and drug the head around on it in a figure-8 pattern. Think he was poor in an Eastern European country somewhere
You might find how handy 4wd is on a tow vehicle. Pulling off the highway in the wrong spot or a grass area at a track. Really easy to get a 2wd stuck unexpectedly.
Yep, 4wd is very handy at times, and it's a must up in the snowy northern part of the country where I live.
It's all in the kind of tires used
@@clembob8004 Me too, but the best thing about 4WD is that is enables you to get stuck in DEEPER snow.
@@craigbenz4835 I've been there, towing a utility trailer up a snowy, icy slope in 4wd. I got to a point where wheelspin limited my progress.....and found that the brakes wouldn't stop it from sliding back down the hill. I was lucky that the trailer steered itself to a berm on one side of the two-track and stopped the backward slide. From then on, if I can't make it up a hill in RWD, I go back down and find another route.
I sub to quite a few big time car guys but I nominate Uncle Tony for President of Car-Tube... I've read so many of his magazine articles while on the throne in my life that it is impossible to not 'crown' him!😁
I think re torquing the head bolts when warm would help.
You know they are going to stretch some.....
This one is a bit extreme but honestly I've seen this on a lot of engines from the late 80's and early 90's. Quality factory machining was pretty bad across the board back in the "cross over" years. The good news was, it's usually an easy fix for the machine shop, but it is an additional step you generally have to take on anything that came out in those years.
Great stuff as always UTG.
What I would also do, when finding heat damage, is measuring the length of the head bolts/ studs, for stretching. Inspect alao the threads thereof in the block, for sediment, which causes false torque readings....in other words equipment shows proper torque, without the pressure clamping the head gasket.
Thanks Tony. Great how to video. It seems like you were fairly thorough. You touched on important things to look for at time of tear down. Nice job. 😊
Good idea would be to check the depth on the threads in the block in that area
I run a bottom tap in all threaded holes. Running a bolt into the last few tapered threads will throw your torque readings way off! 👍
Back to basics - moving hasn't damaged focus at all.... welcome back.
New shop sweet. I guess it's raining outside.
Well explained Tony. Thank you.
Love the basics here. Watching more often now. 😊
Appreciate you addressing the tips and tricks on all your videos, you cover all the basis, do not worry. We love ya!!
My favorite type of videos, learning from your years of knowledge and experience.
That's why we go back over the torque pattern pattern til none of the bolts move.
36 on an N14, my new electronic torque wrench had over 400 pulls on it by the end of the day for the first torque.
This video brought back memories of a brief period when I was in a factory with endless overhead conveyor system that was loaded with empty tin cans. Good content, valuable content. The machine marks are at different angles! I would expect it to be done in one straight pass.
Another interesting thing if you are trying to locate whether you have a burnt exhaust/intake valve.
(This takes into account that you DO NOT have any blown head gasket issues of any kind and or other mechanical issues, this is strictly testing how well the valves are sealing.)
(Blown head gasket top later...)
(1) Hook up your shop air to the spark plug hole of your suspected cylinder.
(2) make sure the the cylinder is not on exhaust/intake stroke, you want the cam & or valves at rest on the base circle for both valves, depending on how many valves your engine has.
(3) open the throttle MANUALLY, and give a listen, if you hear hissing or air rushing noises, your intake valve is leaking.
(4) do the same for the exhaust, go to your exhaust pipe and give a listen, if you hear air rushing in the exhaust, means the exhaust valve is burnt & or leaking.
BONUS add on: You can do the similar above to locate a leaking head gasket also, head gasket issues will manifest in bubbles in the radiator / coolant reservoir.
This signifies your head gasket is blown.
(Tidbit I left off, don't set your shop air regulator too high, or the engine could rotate, and potentially fire the cylinder)
I worked all day.. got caught up on my news and politics... got pissed off as usual. ...(I'm Canadian so...Ya ...Ouch)... But now... Uncle Tony is here to reel a guy back in with a cold beer and and some wrenchin' ....Thank you Sir!!!! ZEN TIME
Thanks Tony, your a great teacher. Love your content.
A hundred thumbs up for emphasizing that the most important diagnostic tool in the shop is YOU--eyes, tactile feedback, brain analyzing evidence, smell, sound...heck, some people probably even taste at times. Why would you limit the efficacy of that diagnostic tool just to save an inconsequential bit of time?
You can tell if a carb'd engine has been running rich for a while or flooded cause the oil will taste like gas
Very cool and very helpful. I learned a lot , Thanks .
Once I got a Ram 2500 with a Cummins. I never considered towing with anything else. The weight and stability at hi-way speed is fantastic
Back in the late 80s and 90s, me and my dad use to play with those.mopar 2.2 and 2.5 turbo engines. What a ball. I had alot of fun with all of that stuff. Blowing people away with their, much larger, engines that were all souped up. We use to blow cylinder heads left and right. It got to the poi t we just kept a few in the car and I could just loosen up enough stuff to slightly lift the head and slide out old gasket, slide in new gasket. Tighten head and everything back down and weeehaaa !!!!! I think I was doin it in a hour too hour and half at that point. No biggie, just swing i to a store parking lot and knock it out. Many many times We melted out the aluminum between cylinders on the heads, usually only happened if drove on it much. Sometimes jist a days driv8ng on it wpuld burn it out. We melted alot of pistons, trashed alot of blocks, torched many heads. We had alot of fun.
Ill never forget the day I rolled up next to a glhs omni at a light. I believe i was in a manual turbo daytona 2.5. Light turned green, i let the clutch put and that guy was half way to next light, that was half mile away. It was unbelievable. It almost looked fake. The way that car launched and accelerated. Ibe been in cars that blurred my vision due to the rqte of acceleration, that GLHS omni was insane.
A workshop in Adelaide, South Australia, when those cleaner's came out said he was having to have block's decked because they were rounding thetop of the bores ,having them return for warranty blown head gasket,thanks for sharing, all the best to you and your loved ones
Another great tech session, thanks again for helping out the community.
That is not a factory grind on that head. That's been through Bubba's "machine shop" to get it "good enough" and slapped back together. That's also the beauty of the 4.0. It's pretty resilient to butcher jobs.
Mechanic probably tightened the head in a circular pattern always starting with cylinder 6 and clockwise. Clockwise is critical.
I have had splits in the middle of head gaskets, but that is an epic gap wow. It was ran with that blown for awhile to burn that much gasket away.
Great explanation U.T!
Oh yeah, and I get what you mean with the head bolt tightness. Last Hemi 6 I pulled down (see video) some felt right, some I swung on with 2 hands on a 3' breaker bar, and a couple undid with one hand at a foot leverage.
I was lucky enough to have a 1896 Cherokee 4.0 high compression that I used as a tow car and everyday driver. Drove 100 miles a day and towed an old 18ft Whaler on a two wheel trailer. When I got it I put a tranny cooler on it. Never had an issue with it. It towed like the trailer wasn't there and that is a heavy old boat. Great vehicle.
Great video on bad factory machining and cylinder head warpage.
Sounds like you're getting the rain there that we were supposed to get here. Georgia never really materialized here, though.
Also that cutter was moving to fast in both directions. 💁😱and to think it’s been running for 240k?
I've been wanting to install a new motor on my XJ This will definitely help me make sure i get it done right. Well appreciated. We appreciate you uncle tony
Another thing I might be concerned about would be the catalytic converter possibly being damaged due to unburned fuel passing out of those two cylinders that were trading compression. It depends on how long it was run like that, and the miles on the cat. One other thing....I had a customer years ago with an 84 K5 Blazer 4x4 with a 350. It had leaking valve stems, pretty badly leaking, like lots of smoke on startup, you could sometimes hear the valves fluttering, and sometimes misfires. Pulled the heads, and due to the 130k miles on the engine and the amount of ring ridge at the top of the cylinder bores, advised the customer that I would recommend a rebuilt engine be dropped in. Crate engines were cheap back then, like 1200 bucks for a GM rebuilt. He declined, and just wanted the heads done. Sent the heads out, had them completely rebuilt, re-installed them properly, and the thing ran like crap! No power, tons of blow-by, burning oil, etc. Sealing up the top end had revealed that the rings and/or cylinders on that 130k mile 350 were indeed toast. Ended up selling the customer a complete rebuilt GM crate engine, and he knew he was advised he needed that in the first place, so he paid for both jobs. He was a good dude, and a good customer, so I cut him a break on the labor. Live and learn!
Yeah, never do "just a valve job" on a high milage engine. The leaky rings could keep up with the leaky valves, but not with ones that seal.
@@craigbenz4835 Yup. That's what I told the customer when I saw that ring lip. Now he knows!
Thanks for teaching me to look closely to head gaskets!
THANK YOU Uncle Tony!!!. Yesterday's and today's videos make me feel like a parts washer in your shop on a slow day. The Master has the time to show the ignorant soul how to do things. I LOVE it!!!. All that was missing was the Stunt Carb!!!
RRoooooooLLL Up Your Windoooooooooows!
there is a freebie way to hand plain a warped head. An aluminum head will take a few hours to plain it by hand. I did it to a little Mazda 4 banger that lost compression in the 2 middle cylinders. I was able to plain it within mininal specs in about 3 hours. I broke off a piece of a knife whet stone. I used a straight edge and feeler gauge. I used a sharpie to mark any high spots and gradually honed those high spots down. it was a slow process. But it didn't cost me or the car owner additional money to send it to a machine shop and I didn't remove the entire surface of the head. If it warped again in the future, it was still repairable. That little car lasted a long time after I repaired it
I've rebuilt about half a dozen machine lathes from WWII, the last about a decade ago, I scraped their surfaces flat and true to a surface plate and various straight edges, I suspect you are describing the same process? I've done a few cars, but sent the heads out to be surfaced, never tried scraping to flat.
You just tell the customer it needs a rebuilt engine, and everything gets fixed. 🤣🤣🤣
Wow. My 9 year old boy said the head looked like UT was surfaced with a Stihl chainsaw.
The gasket looked like it was coated pretty good in bars leaks. I bet you have a heater core in your future.
Check the water pump impeller and the radiator to make sure it doesn't have any underlying causes for overheating.
You're a great teacher Tony. Love what you do. Keep the videos coming.
I like using plate glass with sand paper glued to it with spray adhesive to clean head surfaces. I actually straightened an aluminum 4 cylinder head that was overheated slightly a couple years ago using that method. You have to be careful not to lift or push down, just back on forth and keep the sandpaper fresh using acetone or lacquer thinner to dissolve the glue.
I dont think i have ever seenmarks like that on a cylinder head from machining like the ones on your 4.0 liter head what the guy was say ya we can get one more head out that cutter.
Friday arvo
Probably the definition of a 'Friday Afternoon ' job...
"Do I want to put fresh stones in this cutter...? Nah, it's near clocking off time!"
We joke about these things, but there's the evidence.
@@StarlightWorkshop0z beers getting warm gotta hurry.
I have seen marks that bad on factory parts. Quite often actually. Grinder marks on the head and block. Cutter marks on valve seats. It's actually very common. An inline 6 cylinder engine head is more likely to warp than a 4 cylinder head or a V8 head. The longer it is, the weaker it is, and the easier it is to distort. And as bad as those grinder marks are, the head gasket did not leak there. It leaked in the center, at the weakest point, where the head is more likely to distort. I believe you said that engine had well over 200,000 miles on it, and those miles were put on it in that condition, up to the point where something caused it to distort in the middle. But the grinder marks didn't cause that. But you did bring up a good point. People still complain about how unreliable '70s cars were. And that is actually true. But it is not because of bad design. '70s engines had a great design. It was poor quality of finishing and assembly that caused them to fail at such low mileage. Ever looked at the service manual for a 1970s American engine? Especially GM? The tolerances were TERRIBLE. You could have one crank bearing too loose, and the one next to it too tight, but the manual said it was in spec. Properly built, a '70s engine will run past half a million miles.
I learned a lot Tony coming an old Mopar guy myself from a long way back I’m talking like an early 70s. My first car was a 1962 dodge dart with the poly 318 in it and I wanna tell you right now I shut down more than one small block Chevy with that car it was stock I’m not gonna tell you it was world beater, but it ran good got 18 miles to a gallon anyhow reading the head gasket like you talked about the dark spots in between holes. I learned something there I knew obviously the section it was blown completely out but anyway thank you again Tony you’re a good guy. Oh by the way, I got a stage five hemi conversionwith him Mopar Siamese cylinder block Kieth black crank Crower for rods. Have a good day guy.
Great video Uncle Tony, well explained, thanks.. Do you have something special planned for Kiwi and Steve O tomorrow night? They sure deserve some kind of reward for making that trip and not throwing in the towel.
I think that head was surfaced with a skill saw or a angle grinder at best.
Angle grinder wouldn't have been as rhythmic in digs
It's surprising just how bad the machining can be on these heads. I also pulled apart a riding mower head that was about the same "quality", some time with a sheet of glass and working my way through wet n dry sandpaper grits fixed it right up since it was small and aluminum.
I'll be excited if you decide to do a stroker build. Were you thinking about doing the 258 crank swap or is there another way?
This was really good information and easily understood from a novice like myself just trying to learn
Maybe you could give us a couple tips on angle torques for head gaskets that require that? Keep up the fine work there!! Thanks for helping the DIY'ers!!
Hey Uncle Tony. Thank you for this and the last video. This is Exactly what I was hoping for when you started the jeep motor rebuild from a year or more ago. 1st rate. Chuck in Florida. Thx for all your tips Sir!
Appreciate it.
Only thing you forgot is that you should look for cracking across the valve seats before even considering looking at anything else. Yes, more common on cast iron - but might as wellkeep it on the checklist.
Must be nice to be able to "swing by the local machine shop". They are a rarity around here in Seattle area. The one I know of is booked solid.
We used to have a bunch of 'em out in the South End... out within range of S.I.R. but like you say... 6 months out to get a pair of small block Mopar heads freshened up. Just insane. I sent mine out of State to Idaho to save over 100 days of waiting. Then I moved to Pocatello! :D
Another great video uncle Tony! You go deep on engine work and that makes all the difference! Its the details that can get you and you definitely have the mind set and experience to get it done right without braking the bank. That takes true wisdom! Thanks again brother! Congratulation's on your new shop! Very nice man. You deserve it!
Love these vids mate! Thank you!
Yep just what I suspected, which tells me you have a radiator problem. Since you are going this far Tony, might as well yank that radiator and have it cleaned out at a radiator shop. As everything you just said, points to the same culperate that got my 351W that I dropped into an old 1972 Ford F-100 which was a bad radiator.
Thanks for the knowledge. I have oil in my coolant on a 1996 Mercedes C220 and I suspect a head gasket so I am learning as much as I can about blown head gaskets etc. I will be working on it in my driveway under a tarp so the basic stuff is what I need.
It’s great to see more consistent content popping up, and I especially enjoy the xj projects. 👍👍
Hey Tony would the head gasket or head still be suspect if the compression is all good but the car overheats
tony , that head and block are likely warped , probably left the factory warped. crank may be warped rods could be bent too----it may have been overheated and run hard--
Being a qualified mechanic from Australia for 30 plus years , iv never in my lifetime seen a head that badly machined , surly that wasn’t done at the factory, if so it must have been Friday afternoon lol
PS I sent an email a while ago asking for help sourcing parts for my 69 dodge Phoenix , cheers.
for someone that rides at air-cooled Harley-Davidson
I would say either the head is warped or the studs pulled out in middle
There is a bit of carbom build up in mr 4.0 liter.
You can use cookie wheels but you have to make sure your using a soft kinda (i use Norton orange wheels) and trying to keep it more flat, not digging in and only if your going to use a composite gasket and the head is iron
Leak down tests are mainly for valve seat seal. Compression test and leak down will indicate ring wear or blown heat gaskets. Just listen while doing either.
Man that might have happen 2 my better half on way 2 work 2 day on our qb dakota 5.9..
Hoping not.. truck has enough problems, praying!! Maybe worth giving the blue devil a shot I had it work on my dad's old danger ranger
A cinderbloc, or ideally something equally heavy but smoother, with wet 600 grit paper can definitely do the job.
Great information. Thanks Tony.
Tony, is it possible the head gasket failed as a result of crazy timing issues causing detonation as the distributor was self-destructing?
It failed because of numerous heat cycles and the head had a tendency to warp, probably.
You got those subjects on test & diagnostics well covered without a script, Tony. Shame about the head on that 4-liter. I had a 250cid, straight-six with a pick-up truck, 3-on-the-tree in a 67 Chevy-II that almost felt overpowered for that little shoebox Nova. My Dad would drive it and only use 2nd gear in town. Also, not surprising your Jeep was still drivable on 4 cylinders since the 250cid straight-six with two cylinders chopped off was basically the design of the 150cid, Iron Duke, 4-cyl that I had in a 79 Chevy Monza. Iron Duke wasn't impressive for much other than its tenacity. Could not kill the old Iron Duke or the bigger brother; the 250cid, Chevy straight-six.
Excellent information, thank you.
every head gasket I've seen blown had combustion gasses getting into the coolant, one whiff of the radiator cap was all I needed to tell me a gasket was bad or head/block cracked.
with exception of having a cold or severe allergy days. lol
All the failed head gaskets I've diagnosed, I've detected with my nose. There's that characteristic smoky bacon scent, and the header tank boiling up like a kettle to confirm.
Smelled that on an old impala. Didn't have the money or the knowhow to fix it, so I junked it.
This was great, thanks!
I have water in the oil of my marine engine, Crysler 318 reverse rotation. The spark plugs in my cylinders 6 and 8 looked like new. This is how I determined what bank of cylinders were leaking water into the oil.
Your right on I do this all the time sad😢 it's factory cut that way and don't use the cookies😂 to clean head gaskets or any gasket area
That one end of the head looks like a chevy that has a wheel hopping issue.
Homie you are talking about closed deck iron blocks, you get those open deck aluminum blocks like honda the liners can drop and you need to deck the block.
A better option than sandpaper is a cheap double sided sharpening stone. They are only a few dollars and will give you a far crisper visual of flatness. The sandpaper has a tendancy to follow the contours a bit.
Hey Tony,
Tim here, i like the new shop overall, more compact, more concise......one thing, maybe insulate the roof, wether on top or bottom, to reduce the rain noise....my first thought was to add some kinda tar paper/shingle, OR put somethin in the ceiling..... the rain noise is loud....... just a thought my brother........i personally wud want my shop a bit quieter.......space seems right up to par......can we quiet down the rood noise in some way??.... ok, i mite be bitchin out my butt, but, a quieter shop will allow ur focus, and keep vids focused, no distractions!!....Just thoughts