Leaking header question
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Leaking header question Hey guys, I've got an LM7 truck 5.3 with a set of Pace Setter shorty headers on it. They came with paper gaskets and bolts, directions said to use copper rtv which I did, and have had no problems until recently. Have a visual leak at the top of hole 7 (carbon) and possibly more leaking at 5 underneath although its hard to tell. The bolts loosened frequently (Forget the torque value off the top of my head but it was low) and in attempt to get them to seal up I snugged them down by feel which was probably much tighter than the initial torque value. Anyways.....I purchased a set of Percy's dead soft gaskets and Stage 8 Locking bolts to nip this problem in the butt. Stupid question but is it common to have header flanges milled to restore straightness? I had a SBC that did pretty much the same thing. Tried all different types of gaskets including copper. Eventually cut the flanges so each tube was independent. Still had problems and ended up buying new headers. Would like to avoid all the BS this time around. Just looking for insight I guess. By the way I went with Percy's cause I guess that was all the rage and then poking around the site I see a lot of guys saying Remflex is the best. Im sure they are both good in their own right.
I have a machinist straight edge to check them. You can also buy a good quality level from Menards/Lowes/Home Depot that will work pretty well. Even a good quality counter top is usually level enough to tell if there is a problem.
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I've had pretty good luck with the graphite ones, Remflex I believe. Summit has them, no doubt others as well, maybe your local speed shop. They're SOOOOOOOOOOPER thick, able to conform to significantly not-straight parts; and seem to be able to resist the "blowout" that happens to so many other kinds of header gaskets.
As said make sure the flanges are straight.
Stock MLS metal gaskets, stock bolts. Done.
IMO, there is no need to run really expensive or fancy gaskets and bolts. The stock stuff is superior to most aftermarket stuff out there.
Just my .02
Stock MLS metal gaskets, stock bolts. Done.
IMO, there is no need to run really expensive or fancy gaskets and bolts. The stock stuff is superior to most aftermarket stuff out there.
Just my .02
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Joined: Dec 2017
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Problem with headers is, you can straighten em by whatever method you want; they don't necessarily stay that way. Even just the change in temp can make em change shape, let alone the aging effects that make em warp.
Best, with headers, to use gaskets that are long-term flexible and pliable enough, to deal with things that move and don't stay put. They're not the same as manifolds at all, and the same gaskets don't always work the same.
Never had much luck with fancy bolts though... I just have regular old Lowe's stainless ones on mine. The problems I've had with headers over my lifetime haven't really included too much bolt failure, or even bolts that backed themselves out. IMO the "locking" bolt systems are just an expensive solution in search of a problem best solved at its source.
Best, with headers, to use gaskets that are long-term flexible and pliable enough, to deal with things that move and don't stay put. They're not the same as manifolds at all, and the same gaskets don't always work the same.
Never had much luck with fancy bolts though... I just have regular old Lowe's stainless ones on mine. The problems I've had with headers over my lifetime haven't really included too much bolt failure, or even bolts that backed themselves out. IMO the "locking" bolt systems are just an expensive solution in search of a problem best solved at its source.
