Any hints on leaky header gaskets at the cylinder head. The bolts are tight, the gaskets are new, but they are leaking enough to give me headaches and dizzy spells after a drive? Do I need to replace them??
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Unfortunately there isn't much you can do.
You may be able to use two header gaskets on each side to give you enough crush area to seal.
The problem is really the header flanges themselves.
They get hot enough to warp themselves away from the heads.
Don't bother with the high temp silicone.
You will just make a mess and get it all over the tubes and engine.
If you find a sure fix, please let me know too.
Good luck.
You may be able to use two header gaskets on each side to give you enough crush area to seal.
The problem is really the header flanges themselves.
They get hot enough to warp themselves away from the heads.
Don't bother with the high temp silicone.
You will just make a mess and get it all over the tubes and engine.
If you find a sure fix, please let me know too.
Good luck.
Hi. If you remove the header's you can probably get the milled at a machine shop.
Reinstall with new gasket's and they should be good to go.
JOHN.
Reinstall with new gasket's and they should be good to go.
JOHN.
My original headers were cracked where I couldn't see it. I thought it was a gasket leak until I got it off of there. Ordered a set of headers and when I pulled the other one, it was cracked too!
Just something to check if yours are the originals. They are prone to cracking.
Mooso
Just something to check if yours are the originals. They are prone to cracking.
Mooso
...You might be using the wrong gaskets! Have you changed to aftermarket headers? Or still have the factory headers? Are your heads 4V or 2V ?? I know for a fact that the Fel-Pro 'set' will give you 2V header gaskets that will NOT seal 4V head ports. The 4V exhaust ports are shaped like a Large 'square' with rounded corners and the 4V gaskets to match these are hard to find. If you have headers with the smaller oval ports (some do), they, in one case, just barely sealed on the 4V ports and 4V gaskets. Exhaust leaks are one of the most annoying sounds from the engine compartment; and one of the most difficult to completely eliminate. I wish you good-luck with it!...
It's more than likely your weak flanges on the headers. I had the same problem with my old headers. My new headers flange is twice as thick. No problems now.
I also noticed that my old headers have oval ports at the flange when the cleve exhaust port is rectangular. I noticed on my old headers that the leaks were from the parts of the gaskets that did not have alot of contact to the head. Not sure if this makes sense to you but make sure there is alot of solid, flat contact to the head.
Also, summit sells copper reusable gaskets that may help, although I've never used them.
Will
I also noticed that my old headers have oval ports at the flange when the cleve exhaust port is rectangular. I noticed on my old headers that the leaks were from the parts of the gaskets that did not have alot of contact to the head. Not sure if this makes sense to you but make sure there is alot of solid, flat contact to the head.
Also, summit sells copper reusable gaskets that may help, although I've never used them.
Will
They also seem to be coming loose too. The flanges are very thin. My heads are the 4v closed chamber heads. I think I may try new headers next.
Keith,
Although your flanges are thin, you might be able to fix the issue by installing the previously mentioned copper gaskets, and installing Split-Lock header bolts as seen here.
Although your flanges are thin, you might be able to fix the issue by installing the previously mentioned copper gaskets, and installing Split-Lock header bolts as seen here.
I just got done fighting the headers on my trans am. There were a couple problems. When they made these headers they weld a bead around the opening for the header to mate to the head. That does a couple things. It decreases the surface area which increases the pressure as the headers are tightened up. It also keeps them from bottoming out further out which would prevent sealing at the opening.
On my headers (which were new) The gasket was pushed out where the raised portion was. I TIG welded a new bead further out to widen the contact base a little. At this point it would be great to mill it flat and make them perfect but I don't have a mill and chose to tackle it right then and there.
In order to get the surface completely flat again, I ground down the weld with a grinder. After getting near my target I would take a magic marker and mark the entire surface. Then take a flat piece of very flat steel and sand paper (80 grit emery). The highlights will sand off the magic marker. Gently grind the hight lights. repeat. Do this until you can sand with the flat metal and and have an flat contact surface all the way around.
This is assuming you can return and match the original deck surface. I was able to and got mine to seal up with a single gasket.
The other side I did it differently. I put two gaskets together and put red RTV in between the gaskets. I lightly snugged the bolts and let the rtv dry. Latter I tightened the bolts. After running the car and warming it up tighten them up again.
Either way I got both sides sealed up.
On my headers (which were new) The gasket was pushed out where the raised portion was. I TIG welded a new bead further out to widen the contact base a little. At this point it would be great to mill it flat and make them perfect but I don't have a mill and chose to tackle it right then and there.
In order to get the surface completely flat again, I ground down the weld with a grinder. After getting near my target I would take a magic marker and mark the entire surface. Then take a flat piece of very flat steel and sand paper (80 grit emery). The highlights will sand off the magic marker. Gently grind the hight lights. repeat. Do this until you can sand with the flat metal and and have an flat contact surface all the way around.
This is assuming you can return and match the original deck surface. I was able to and got mine to seal up with a single gasket.
The other side I did it differently. I put two gaskets together and put red RTV in between the gaskets. I lightly snugged the bolts and let the rtv dry. Latter I tightened the bolts. After running the car and warming it up tighten them up again.
Either way I got both sides sealed up.