Header gasket leak
Thread Starter
Launching!
Joined: Jul 2019
Posts: 204
Likes: 8
Header gasket leak So I had my heads redone by Lloyd Elliott so they were massively clean. Bought used Pacesetter long tubes. Used percy aluminum gaskets. Torqued to 11 then 18 lbs and install was with engine out of car. The bottom of cylinder one is leaking like crazy. I put a tissue up there and it was flapping away. Anyone have any tricks to these things? Bolts are still tight
Last edited by Jon M; Nov 9, 2019 at 05:36 PM.
Metal gaskets leave little-to-no margin for error for leaks. The flange on long tubes, no matter the brand, are not usually as true as exhaust manifolds. As man-crush said, check the flange/primaries. If you don't want to go that route, Fel-Pro 1406 and retorque after a few heat cycles. See what happens.
I've used and reused again my Mr Gasket copper header gaskets. No problems. This is with Kooks long tubes so I can't really compare your header flanges with mine but mine are nice and flat, no tube protruding through the flange. As far as Torque... Man, I've never torqued a header gasket a day in my life, it's all by feel and you might find if you just tighten by feel after a heat cycle that they'll seal up. It's worth a try.
Using the term as a verb, as in to retighten. Paper gaskets have a tendency to shrink when they get hot, which means loose header bolts which means a potential to have a gasket blow out.
Trending Topics
I have never had a failed exhaust gasket on a car. I do them often on the tractors. Usually it is because of a bolt rotting and breaking or an bolt rotting and stretching.
I find it entirely plausible that it is a expansion contraction issue. But I would believe it has more to do with the mild steel matting surface then the gasket. Maybe after a few head cycles they start to distort or warp allowing the bolts to become loose.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo Eh, Adam beat me to it lol! I'm not even really sure how this turned into an English lesson either. Tighten again or retighten, what's the difference? He gets the picture. I always "retighten" after a heat cycle because both aluminum and copper are warm and more pliable. I can't say I've ever had an issue. Usually the issue comes with the header bolts slowly backing out over time causing paper gaskets to blow. On my Kooks I've always used stage 8 bolts and locks and again, no issues. I could see how this could also help paper gaskets as well. In neither scenario are paper gaskets being used here. Anywho, I still stand by getting the material good and hot and then going over the bolts again to "retighten" but by feel rather than torque spec. It’s sure cheaper than replacing gaskets, less work and may just solve the problem. Jon, give it a shot brotha!
Last edited by Vicious95Z28; Nov 6, 2019 at 07:18 AM.
Paper gaskets have a tendency to shrink far more than a metal gasket, and stay that way. There are piles of threads about those having issues with header bolts becoming loose after installation. All I'm saying is there is a chance the flanges are not true and a paper gasket may be the answer. Especially if metal gaskets have already been used and there is a leak. I'm not blaming the gasket at all. It's just a matter of fact that metal gaskets are not as forgiving as paper if a surface is not true.
I don't think getting a torque wrench onto all header bolts is physically possible in these engine bays. By retorquing bolts it has nothing to do with going by torque spec. Simply another word to "retighten."
I don't think getting a torque wrench onto all header bolts is physically possible in these engine bays. By retorquing bolts it has nothing to do with going by torque spec. Simply another word to "retighten."
Dude, he straight up said he torqued the bolts to 18ft-lbs . I think it’s given that you likely can’t get a torque wrench in the engine bay, especially on a C4. They’re a super *** pain to work on period. I was completely advising him away from even being concerned with a torque spec altogether. Yes, I agree, paper Gasket material is more forgiving, hence why I told him to get the aluminum Gaskets hot so that they’re pliable. I personally do not like aluminum in this application, they just aren’t soft enough for me. I prefer copper.... either way you have to think that even though the flange on the header may not be perfect it’s going to have left an impression. What we’re trying to accomplish here by getting the gasket hot is a deeper bed into the already existing impression. It’s simply a suggestion that may or may not work, just like anything else but if it works for him it just saved him way more time and some money too just for the cost of the little bit of time it takes him to try. Why does there have to be a rebuttal for every suggestion someone makes? Just let the man try instead of turning it into a pissing match of what material is the best for his application! Damn!
Last edited by Vicious95Z28; Nov 8, 2019 at 06:47 PM.
Merely suggesting if a metal gasket doesn't work, try paper. That's it. Not saying anything about who is right or wrong. The "retorque" thing got lost in translation. I thought you were talking of my usage rather than the OP's. My bad.
Thread Starter
Launching!
Joined: Jul 2019
Posts: 204
Likes: 8
Been away a few days and hello replies!! I had the advantage of putting these on with the motor out of the car so I was able to torque them based on GM’s manual the first time. Now I am not so lucky and I am fiddling with a box wrench messing with these things.
I ordered the fel-pro 1406’s based on several other threads. Percy’s had almost an equal amount of votes and they sounded awesome back in Sept when I searched this topic.
In the end, I took the thing to an exhaust shop today and they are going to tackle this leak and weld up the y pipe to the catback since I have a major leak there as well. It was snowing today and I need this done ASAP so I can focus on the tune and it running rich AF.
i do appreciate all the input though. A passionate bunch on here!
I ordered the fel-pro 1406’s based on several other threads. Percy’s had almost an equal amount of votes and they sounded awesome back in Sept when I searched this topic.
In the end, I took the thing to an exhaust shop today and they are going to tackle this leak and weld up the y pipe to the catback since I have a major leak there as well. It was snowing today and I need this done ASAP so I can focus on the tune and it running rich AF.
i do appreciate all the input though. A passionate bunch on here!
I have had equal good luck with the percys and 1406s so you are good either way.
GM torque assumes you have a heavy cast manifold, not a cheap header flange that may or may have warped when welded.
GM torque assumes you have a heavy cast manifold, not a cheap header flange that may or may have warped when welded.
