exhaust headers leaking
 

Hooker super comp headers on SBC ,can't get good seal against heads.Tried regular gaskets,now using copper .Bolts are always coming loose.Even with bolts tight center tubes still leak .Any suggestions?

Re: exhaust headers leaking
 

are your header flanges absolutely flat??? Comp387

Re: exhaust headers leaking
 

Not sure if they are flat.Had headers coated a few years ago ,can't remember if I had this problem before

Re: exhaust headers leaking
 

We have a BB Chevy and also use Hooker Super Comps. Hooker is known for ill fitting poor sealing headers. You have to remember they are mass produced so the attention to detail is lacking.

Take a straight edge and check the flange as suggested in the other post. If you have more than a few millimeters of daylight between the straight edge and the flange I would consider sending them back to Hooker. Also check for cracks in the welds/tube.

If they are an older set, what we do is we use the Fel-Pro high performance header gaskets. Make sure the gaskets are new. We also put an 1/8 in. bead of Permatex Ultra Copper silicone around the header tube/cylinder head interface on both sides of the gasket. Usually we stick the gasket to the cylinder head and then mount the header. You can also put a dab of silicone sealant on the header bolt to help keep them from loosening. Tighten them down snug but don't go overboard. Don't start the motor until the silicone is fully cured. Preferably overnight. The job can be a little messy but it all wipes off when the headers are tightened down. It works well for us. It is an economical fix and worth a try.

Re: exhaust headers leaking
 

If they are an older set and you can't send them back , and all else has failed, you can cut the flange between tubes and they will seal. I've had to do this quite a few times to get even some custom built headers to seal.

Re: exhaust headers leaking
 

throw gaskets in trash, use only small amount of ultra black high heat silicon, bolts will not come loose, they will not leak, you can take all the bolts off and header will not fall off, you should never have an issue.

Re: exhaust headers leaking
 

I'll tell ya what.... on a SBC the ONLY thing we'll use is the STOCK manifold steel gaskets! steel side out! They work you can't tell me any different the engine in dad's old Camaro had 8 seasons on it & never leaked! this is what all my buddys use on their street cars with no trouble! ;)

Re: exhaust headers leaking
 

One thing I used to do with my V8 Vega was to use 2 gaskets stacked, and soak them in water overnight, then bolt them up and fire up the engine with them still wet. They formed a good seal that way.

Regards,

Re: exhaust headers leaking
 

Thanks to everyone for their advice.Going to try the copper silicone tomorrow,what a way to spend my day off of work!

Re: exhaust headers leaking
 

X2 on Greg's comment. They fit the ex port good too.