RARE talk about VALVE GUIDES ( must watch)
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- Опубліковано 3 лип 2024
- RARE talk about VALVE GUIDES
( please watch)
We have a talk about valve guides witch is something a lot of guy don’t talk about. Reasons i like some and don’t like some - Авто та транспорт
I would like to ad that if you use brass guides, ream them out. When you drive them in, the brass ones hourglass and will seize valves every time
I have been building engines for 40+ years. What I have seen, when tearing down a engine with thin wall liners is, that 98% of them are crapola!
Some will say that this is from improper machining or heat related or whatever. Made me think why would anyone want to run them.
At one time I worked at a production cylinder head shop and I asked why we used thin wall liners. The answer was $$$! The cost of them cheap compared to others and they installed feaster and they saved money there too.
As a machinist for many years I’ve done all these techniques and I got agree with you at all points… Keep on rockin
Thanks 🙏
Tea liners are OK for may be a lawnmower but that’s about it yeah they work but they tear up your valve stems they were them I prematurely I had a head completely rebuilt ported surfaced gasket matched my truck ran a lot better I even gasket match the ATS manifold to the turbo I mean I picked up like 5 miles per gallon and horsepower and torque but I noticed about four months later for the truck up and I’m loading stuff up in the back of it and seeing all the smoke what’s going on here huh guess what killed the valvestems this is six in a row jim From kennerdell Pennsylvania
Wow this is very interesting, I knew knurling used to be done with pistons but had no idea it was done to valve guides I figured they were cheap enough one wouldn't need to do it.
ya. used to see it alot.
Guides are cheap enough... Liners are simply cheaper. It's about shaving costs and trying to make another dime, rather than make the engine proper. Many engine builders say they don't get returns, but how many really pull a manifold just to check to see if liners are still perfectly placed? Most often it there are problems again, the owner just drops the car off at the wrecking yard and goes to get another one... The machinist never knows, unless the owner wants it right.
I like bronze best for any engine and pressing them back in which is a pain but it’s my favorite way
Yes I got all the tools for nurrling it but replace them is best
I know the liners have critics, but I tend to suspect that they are often installed carelessly by some shops and especially in less experienced situations (shade tree) because it is economical to purchase a kit.
I don't really see how they can slip until the valve stem expands and drags on the liner, too tight a fit.
I think the slipping reputation comes from fitting either with worn tooling or poor finish. They advertise that you can run tighter valve clearances, which, if you know what you are doing, you probably can, but...
I have seen lots of guy use them and I know lots do. I just don’t like them.
Awesome video. I appreciate your content. I’m actually doing my first rebuild of a set of 906 vortec heads with a beehive spring upgrade was wondering if you had a recommendation or part number for valve seals?
It depends on you guide size. When we do them we cut the boss down to .500 so we can use the a universal seal
the late super engine builder Smokey Yunik totally agreed with you. He always preferred a solid cast iron guide. Knurling guides is just the cheapy approach. Cast iron is as brittle as peanut brittle and knurling is a waste of time
I'm only about 5 minutes in so far but just wanted to say that our high school auto mechanics shop teacher told us back in 1986 that knurling valve guides was obsolete and not recommended even before then, I can't imagine that it's even still a practice by anyone today. 🤔
We knew it was a no no 36 years ago.
Three shops local to me still do it
I have been asked to do it but I just turn job down because I know it’s a patchwork and will screw some one over
I have an engine that ran with no oil for a significant amount of time (received it that way), to not get too detailed, filled it up with oil, noise cleared away after 5-10min, compression ~150psi in all cylinders, I suspect bad valve guides (not seals). lots of shavings were found in the oil filter. is it possible everything else held up but the valve guides themselves are shot? smokes on startup and I just wonder if there's an easy way to distinguish between valve guides and valve seals being bad.
I would say likely not. But I have seen weirder things
I used hundreds of liners without issue to date. But the preparation of the reamed hole in which it is pressed is crucial. Chamfering so the liner isnt ' eaten' by the sharp edges when pressed in. The press fit itself should also be ok. And I prefer to use only 1 broach and then hone to size . As the reamer follows the worn guide bore.... the liner is also shaped to that.... To create a straight round bore...broach 1 time ,then hone. I have 289 Ford sbc racing engines which after 40 hours of flat out racing show no measurable wear.
But if you completely broach a liner to size so the valve stem fits.....Then it wears out fast as the bore has almost no area on which the valve stem can run.
I experienced long ago that a broached guide had , say 0,04mm of play , but valve stem would get stuck half way the guide . Using the next broach created 0.06mm of play....and valve would go through with...hmmm...snug fit...
That made me start thinking about some shops in my area stating : why replace a guide , as after 20k miles you get a head back for repair ..and guides are completely worn out??#@@????
Well.....do it THE RIGHT WAY!!!
I have talked to many people and the companies that make them. For gas engines I would consider using them if I had the kits. But I have seen lots of them move on diesels and from lots of different shops. But if you have good luck with them. I just don’t want to take the chance.
I run a BBF, and have only seen them move, or fall out completely...
Makes sense to use them if wear is minimal, but when the material is too thin to maintain structural integrity, then a high lift cam is likely to push them out. Especially if the pushrods are canted like BBF with a hydraulic roller cam...
the only bronze guide that last are the manganese bronze material, other ones are too soft or they wear out the valve stem.
I also don’t like them as I have seen a lot of them move in a diesel application
I use a lot of Trojan bronze. Hrc30 No problem with those. Though hard to machine ...only with right tools.
'KNURLING' is usually done to keep costs down & is a 'USED CARS' choice.
Curious, on the cast guide. What's the recommended interference fit?
Depends on the stem size but most are .0015-.002
Whats the advantages on stroking a 5.9 and destroking a 6.7
Added displacement making easier to spool turbos. Destroking a 6.7 you end up with a much stronger block
Bronze is soft carbon causes more wear especially the exhaust & diesels generate soot which is carbon
💯 %
It depends on the type of carbon deposits. I have seen diesel heads with ruined guides on intake and perfect on exhaust. Also the other way around.
So 2 types of carbon deposits, at least : lubricating and dry hard.
The latter can also ruin complete engines when ingested through EGR .... haven seen that with some engines. Worn out guides and cylinder bores as the hard carbon deposits got through EGR ( or faulty management of EGR valve, or broken ) into engine...
What do you think of Silicon Bronz VG?
In a full form guide I use them. Lots of guys use guide liners without issues. I just don’t like to use them myself.
Would polishing the bore so it rides as smooth as a wrist pin be a good idea?
I like a cross hatch to hold oil.
@@CUTTERUPROB thanks. I just took my heads apart and the exaust ones were looser than the intakes. Is that normal for more oil on the hot exaust valves?
I'm from the UK and we use them on all the b series and isb engines I've never had a problem with them they have always worked well I've only ever seen them mess up when the installation process has been messed up and it's not had enough clearance from the stem to the guide we did have a guy that was an ex pat that moved from the UK to the usa and moved back and he said that you guys always had problems with the k line guide liners he had a theory that it was because of the climate which maybe true in some states as they are extremely hot in summer months and I've probably done thousands of isb and b series heads and we don't get this problem so could be true who knows would be worth trying it out. and brass works well for petrol engines VW use brass guides In the diesel engines and they could do 30k miles and be knackered seen this before good video is that b series head a USA head or a Brazil head ? I once did a west Germany b series head
ya i know alot of guys use them but after i have seem so many move. I am afraid to use them just in case, i am not sure on the head now did the video a while ago
👍👍
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I have worked in 6 reco shops here in Australia and used all 3 types of guide. You failed to mention that most cyl heads actually have guides that can be removed and replaced with genuine parts or aftermarket. As for that thin guide liner most likely a k line guide i have found them to be highly succesful and a workmate of mine that used to rebuild the engine of a funny car with a keithblack discovered that if he fitted cast guides he could get one meeting out of them but the klines would last around 4 meetings. Also we had a car come in that had a squeek in the top end and we discovered that the mechanic that put it together had messed up something and the squeek was coming from the guides as there was no oil getting to the top end. The old volkswagen bugs used to use bronze guides. Some of the kline kits i have used came with a knurling tool to run through the guide to give it a line for lubrication, some use a reamer to take it out to size while some have a broach which i prefer as it gets knocked through the guide but does not remove any material so theoretically it should make the liner a tighter fit.
Many v8s and diesels in America with cast iron heads don't use replaceable guides, so there is no 'failure' in mentioning anything. The subject simply doesn't apply to heads with replaceable guides.
What type of person cannot see another view aside from their own, then tells others they are wrong? You say you've worked at 6 recon shops, showing your instability, and showing lack of wisdom, so the consensus is the right answer would be 'fool'...
Elementary, Dr. Watson, elementary...
I’m about to do a head gasket on my 12v with 270k on it. At this mileage should I do the guides or run it?
Depends if the head is worn out. Some are some aren’t and that mileage
I’m hoping they are not worn out. The original owner was an old man that left the truck stock and never reved it past 2k for 25 years.
I had a cylinder head for my Dodge rebuilt and I told the guy distinctly please do not use those steel key liners because of those are very hard and they’re very hard on valves what’s the jag off to use steel steel key liners and probably eight months later my engine smoking real bad again on start up and now he did a real nice job on the other stuff beautiful valve job and he and when I took the head to him he said he would have a ton on a certain day it was done and it was right what he said it would be pricewise but it ruined all my new valves and basically I had to have another Val job done so I just bought a Hamilton cam stage to head instead but anyway
That one valve you were showing I’m familiar with the cast guide and with the little worm groove going down they were very good valve guides of factors to my stage to Hamilton Kim’s head I wish it had them in right from when it was new anyway yeah yeah don’t use those key liners stay away from them no good
ya i am not a fan myself
My dude... May we introduce your people to punctuation.
Tea liners have their place maybe a card is strictly going to be run down the strip or it’s not gonna get lots of miles on it but I just sooner have a good quality bronze valve guide you get best of both worlds your valve guides are excuse me your valve stems don’t wear out as often and for the guy who doesn’t like me like using punctuation, anyways K liners I wouldn’t use them in a lawnmower engine yeah I know they work in the reason why a lot of machine shops use them is cause simply put their cheap OK but the consumers getting fucked my brand new valves and my old cylinder had my stock head ruined ruined in about 30 to 40,000 miles or less so they can take key liners and shove them where the fucking sun don’t shine this is six in a row jim From kennerdell Pennsylvania
Are you on drugs?
I use all three and have seen all three have issues. The bronze liners work just fine, it's the install of them that the errors mostly occur. Guys stuff them in there to fast and finish sizing by broach. No trimming, sharp burrs on the ends and just plain rushing through the job. Then stick a worn valve back in. Hundreds or mabye even thousands of heads with them already in have come through my hands and only a small amount had any real issues. Thing I like the most about them is you can size them to your desired fit whereas the cast guides with sizing material never seem to be in stock. So your stuck with the pre set diameter of the guide which is pretty well always on the high limit. I still use hundreds of theme yearly, just a personal complaint. I find some engines prefere one over the other and do quite a bit of engine hobby for myself with some r&d in there. Not long ago I had a 302 I done for mysel on the bench for inspetion and had cast guides and liners mixed in. The cast guids worn more then the liners in that example. Years before I had torn apart a 350 I been running. It had liners and a couple were worn through the liner and into the remaining guide material. The rest were mint though, so no explination there. Maybe my install was the culprit. I prefer cast guides in diesels even though I no longer work on them. I use liners in most everything else. After thousands of heads, no one has returned with a complaint(and I'm in Lower B.C. now, complaining seems to be a social expectation here lol). With my own experimenting though personal builds including daily assult, bracket racing and many years of circle track, I have found no reason to not use a liner. As for knurling, that is hack lol. Proud to say I have never sent out a knurled guide, or piston as a repair. Replaced many though, so I know it was a common thing through small time engine shops and garages/hobby guys.
I do know lot of guys that use them liners. I just have never liked them for how many in diesels that have moved or stuck to the valves. I sure a lot has to installer just like anything. It just give me the Willy when I see them. On the guide sizing. I have the same issues. I have all my common ones custom made for that reason.
Hey could you send me a message on IG
Please
@@CUTTERUPROB yea, I've seen quite a few issues with the liners in diesel truck engines also. Seems they don't like them. The shop around the corner from me uses them and says yet to have an issue though, so who knows. They do a lot of Powerstroke and Cummins builds though, so I guess they would have had feedback if having issues. I'm with you though, prefere cast in them.
I'll shoot you a PM right now👍
I have had 3 sets of Ford 460 heads with guide liners, and 10-12 of the 16 in all three sets have moved within 10,000 miles. One set had a slight overheat from blowing a block freeze plug and it ran for 1 minute back to the shop. 4 liners came out to the head of the valve. I found this out later when removing heads for a little more porting work.
You will never know if one is sliding out until it has ruined the head. Nobody removes the exhaust manifolds to see if the liners have shifted any, they run them until they hear a problem, or sell the truck.
Great for Honda civics not 30k diesels
VW Diesels use brass guides
bronze guide is different then a guide liner, i just dont like the thickness of liners
Ya those valve guide liners are a hunk of crap even on a small block Chevy I’ve seen problems with them
Good guides aren’t tht much more money and the head (s) are already on the bench might as well use good parts
The install has lots to do it. But it give me the willy’s to have spilt guide
Some machine shops set you up with guide liners, and if the head overheats, the liners come out. And then it is your fault because the head overheated. I had one set of Ford 460 heads rebuilt by the same shop, and they put on a heat indicator to see if they had to warranty their work or not. Apparently they can make up a system where they set rules of quality standards. No part of a cylinder head should never fail because it ran a little low on antifreeze..... guide liners are a guaranteed failure if you ever have a problem with a heater or radiator hose later on, especially in a performance application.
If you respect your own wallet, or your engine investment, run away from anyone who tells you guide liners are just fine. If you use your car outside the likes of Grandma's driving, liners will only gain you wreckage.
yep thats why i don't like them. lots of guys use them and have good luck i just not in to it
A lot of shops will use heat tabs the biggest issue with overheating is cracking heads especially diesels, also tends to cause the rings to lose wall tension as well so you can fix the head but may end up with compression or oil issues.
@@grantreid8583 very few (generally speaking) diesels crack cylinder heads. Some heat tabs melt at 235° F, which is where some diesels operate. Cylinder heads don't crack at 235°, and sometimes they don't crack at 275°... but improperly broached guide liners will fall out with heat. Heat tabs are a cop out because they don't show evidence of their work being proper, they just show the head got above a certain temperature. And I assure you that every valve seat that has ever fallen out has experienced temperatures well above that of heat tabs. Heat tabs should melt above 260° F, or they are merely a tool used by the guy who doesn't want to stand behind his work or do his work in a way that maintains integrity... Today's heat tabs show the intent for greed, not prudent workmanship... setting your own boundaries of 'overheating' at barely above operating temperature is evidence of such greed. Prudent workmanship holds up in all working engine conditions, not just conditions of the machinist's choosing.
@@Faolan161 I don't know where you come from but i once worked in a country where the biggest % of vehicles were diesel work vehicles and most of our work was repairing cracked diesel cyl heads yes some brands did not crack but a lot do especially in a tropical climate. Toyota were the main culprits mainly because they were the most common but even in cold climates and hot climates i have repaired quite a few catterpilar cyl heads that have cracked with some models being quite common to crack. So to say it is not common for diesel cyl heads to crack is completely wrong just take one into a hardworking enviroment and don't look after it and it will happen. There are also lots of things happen to the rest of the engine in these conditions as well but i wont go there now.
@@grantreid8583 just because they do crack doesn't mean it is common. Just because you worked at a machine shop where you saw a lot of cracked heads doesn't mean it is common. Common would be cracking a head at 100k miles, or maybe after 2-3k hrs. When people drive them into the ground and get serious usage out of them, and eventually crack a head, that means it is not common.
Common is the Subaru boxer motor losing its head gasket at 100k miles, not at 200k+...
Make sense?
Just because you worked on a lot of old equipment that wasn't well maintained doesn't mean diesels crack heads often.
Geez get to the point
I wouldn't do it, I wouldn't watch this video, it's my oppinion, I wouldn't like doing that, I wouldn't watch this, I wouldn't do this, I wouldn't see my self doing this...christ why didn't you just show the thing you would do. Would have been a shorter video
I do have videos on how I do it. Guys asked for a video why I don’t like these. Thanks for the comment
@@CUTTERUPROB well if they ever get into a situation where they use one of those wrong methods they will find out your point of view about 10k miles later haha