Exhaust header copper gasket - when to replace?

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How often should the exhaust header copper gasket be replaced? Every time the pipe is pulled? Once per season?
 
I will reuse them until they start getting bent out of shape a bit when removing them. I have never had one fail however.
 
Using high temp Orange silicone sealer sure helps them seal. New or used.
Not red, black or clear !!!! Orange
 
Not sure if this would be a tech item for the 206 but on our animal headers I run a fine file across the bottom of the exhaust flange to help flatten it out.
 
Why use the gasket at all?? I don't recall the rules state that you had to use a gasket. Am I wrong?? Use some high temp sealer instead.
 
gary10 said:
Spoiler alert: you need to use silicone with the copper gasket anyway or you’ll see where it’s leaking from when you take it apart after running. No gasket and a light film of high temp is all you need.
Click to expand...

For the most part - I'd agree with Gary
-- HOWEVER, if you've ever had the ex bolts come loose, you know the damage it can cause to the port face (also could be interpreted as illegal.)
That little gasket could save a head for you.
 
I consider it least likely to ever come loose when there’s no gasket but damaging the head is a good point. However, I’ve yet to have one ever come loose since switching to no gasket. And if a tech guy lacks even that much common sense to consider a DQ then he shouldn’t have a job for much longer.
 
CarlsonMotorsports said:
For the most part - I'd agree with Gary
-- HOWEVER, if you've ever had the ex bolts come loose, you know the damage it can cause to the port face (also could be interpreted as illegal.)
That little gasket could save a head for you.
Click to expand...
Most of the time the header is coming loose because of gasket degeneration. Copper is certainly better then other materials but using only silicone and properly safety wiring is the best way to go. I haven't used a header gasket for over twenty years and have never regretted it. That being said sucessful racing is always a matter of obsessive preparation. If you end up with a loose header it means you have neglected proper preparation. My brother would always say Proper Preparation Prevents Poor Poor Performance (the 6 P's).
 
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I haven't found it to be the case where the gasket causes the bolts to come loose (when using a copper gasket) - true with the soft graphite, etc gaskets, yes.

We're dealing with different metals (steel and aluminum) so they're expansion (and cooling) rates are considerably different. Running the gasket or not doesn't seem to make a difference in that regard. You're simply introducing a third metal - (copper.)

Aside from a crash, this thermal expansion and contraction is the leading cause for the bolts to come loose. The threads stretch over time (heat cycles) and you're left with loose bolts. Couple that with over tightened bolts, improperly safety wired bolts, poor brace installation, etc only makes matters worse. Of course it doesn't help that that corner of the head pulls down over time as well -- with rigid bracing, that puts more strain on the header bolts too.

I totally agree that poor maintenance and preparation would prevent this (gasket or not.)

Another thing I'd be concerned about with no gasket is the sealing surface of the header flange. Some are certainly flatter than others. If you ever have to change headers, the next flange won't be exactly the same as the previous one, and the imprint that the previous one made on the head will be slightly different. Really, there's enough movement just in the bolt holes to see where the header will not fit up exactly the same two times in a row (that means any time the header is removed - for tech, head rebuild, etc.) that ex port sealing surface has been compromised, you'll have more opportunity for leakage.

Not trying to change minds, just something to consider.
 
Chipg56 said:
Agree, silicon and no gasket.
Click to expand...
The reason to use a gasket is because when the pipe comes loose (and it usually does at some point) the pipe rattling around on the head will really put a hurtin on the aluminum head surface.
 
Having build many dragbike 4 cylinder engines with copper head gaskets. Copper gaskets get hard after torqued and ran, then can't recompress the next time you use them. For the best result they need to be annealed before being reused. A propane torch ran over them till just a dull Red does the trick. I used to keep a 1/2 dozen of the exhaust gaskets on hand. Along with safety wiring the proper way. I never had a pipe just come loose that was not also properly supported.
 
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