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Anybody use Permatex Ultra Copper on headers?

What do you think is the cause, Craig? Warped/damaged header flange? You could double up on the soft metal gasket, too.
 
Horseplay said:
What do you think is the cause, Craig? Warped/damaged header flange? You could double up on the soft metal gasket, too.
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I'm not real sure. I had the header off to work on the steering (remove the gearbox), after I put it back together I couldn't get rid of the exhaust leak. I have changed from the aluminum gasket I had on there to copper. It helped but still some leak. I have been re-torquing the bolts and again I can make some difference but not completely eliminate the leak.
The weld beads around the header flange are not that flat. I am guessing that it's just hard to get a good seal.
The headers are FPA. He sent a thick gasket when I bought them and it sealed good at the time but the gasket burned through. I tried stock felpro manifold gaskets but they leaked too. The Aluminum gaskets had been working pretty well but when I removed the header I could see where they had been leaking as well (blackened area). The leak is not super loud but it annoys me.
When I pull the header again, I will put a straight edge on it and see if it is flat and maybe flat file the welds.
Attached is a pic of the header when new in August of 2008.Picture 025.jpg
 
the Sanderson headers on my car do not use a gasket. They call out for a bead of RTV to seal the headers to the head. So far, so good. I just saw a program on TV this weekend where they were also sealing headers with copper RTV, supposedly good for up to 650F.
 
I can get some of the Ultra Copper RTV for a little over $7 at Advance Auto... thinking I may try this and the remflex gasket?!?
 
Use of a RTV doesn't sit well with me. I can see all kinds of reason for failure starting with surface adhesion. How many times have you seen a failure with it used as an end seal on a manifold installation? Seems an exhaust application would be even more prone to failure given the higher temps (thermal expansion, etc.) and pressures.

A thicker soft metal gasket seems much more suitable and stable.
 
Horseplay said:
Use of a RTV doesn't sit well with me. I can see all kinds of reason for failure starting with surface adhesion. How many times have you seen a failure with it used as an end seal on a manifold installation? Seems an exhaust application would be even more prone to failure given the higher temps (thermal expansion, etc.) and pressures.

A thicker soft metal gasket seems much more suitable and stable.
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As I stated above, it is what Sanderson calls for. It may be more appropriate for thicker flanged headers where you are less likely to get much, if any, movement due to heat. The Sanderson headers may use a different flange design than other, I don't really know. I just know they don't leak.....yet!
 
kb3 said:
As I stated above, it is what Sanderson calls for. It may be more appropriate for thicker flanged headers where you are less likely to get much, if any, movement due to heat. The Sanderson headers may use a different flange design than other, I don't really know. I just know they don't leak.....yet!
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You just have superior skills, Ken. :rolleyes:

I think you're right about the flanges. With a good 3/8" or better flange and a good head surface I can see it working. Problem is most set-ups have neither of the two.
 
I'm in Seattle this week but my wife says the new gaskets have arrived. I will install them this weekend! Man I hope they work. If not I am just taking the mufflers off and running open headers leaks and all
 
I am home and the gaskets have arrived. I plan to install this weekend. I will let you know how it turns out.
The package says not to use any sealer so I will just install straight up
 
Craig, I still have that power seat track with your name on it. A Saturday road trip to Russelville would not be out of the question, if you still want it.
 
Gary! I am sorry I completely forgot about that!!!
You are welcome anytime!!! I could take you to lunch or something!
 
It's all good. Do you still have the same phone number? 270-847-****. I can text you in the morning to confirm.
 
installed the Remflex gaskets today, that fixed it! We will find out on the Power Tour if they last!
you can see on the copper gasket from drivers side where it was leakingheader gasket.jpg
 
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