Exaust leak problem.

Rat Rods Rule

Help Support Rat Rods Rule:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

maddog

Here he comes to save the day!
Joined
May 13, 2007
Messages
864
Location
SFV Southern California
Had a pesty exaust leak so I replaced the gasket and round flange gasket.
It was worst than before.
Took off the header and discovered that a bad port matching job left a hole outside the gasket.
Welded up the headers a bit and ground a new surface, sanded it, then stoned it and checked it for flat.
Re-installed it and it was much much better but for about 1 min after starting the engine you can still hear a pst pst pst pst.
Then when things heat up it is fine.
Bolts are all good and tight.

Whats going on here?

Dont realy want to take it off again just to look at it, but I may have to.

Any ideas?
 
Hey Maddog,
Which engine is this you are talking about?
Was the bad port matching job only on the header or could it have been on the head side as well?
 
it sounds to me like when the headers get hot, they expand just enough to get rid of the leak. or it could be the gaskets (more likely). my truck has a sbc and it did the same thing with my stock manifolds. i had cheap gaskets on them though. when i switched to the headers i bought some decent hooker gaskets and i've never had an issue (in the three or so months i've driven it like that :D)
 
I had the same problem with a BBC with Merlin heads. I was using Heddman shorty headers. I went to "Earl's Supply" (of braided lines fame) and got some header biscuits. They can be trimmed to match the exhaust port. That finally cured my problem with exhaust leaks.
 
I have found those stock SBC exhaust gaskets work GREAT!! You know the ones, They are perferated metal composit. They are like $2 for the set. The good thing is, They are hidden and you just loosen up the header bolts and drop em in. The Hi performance LT1 gasket has the largest opening. Try em...You`ll never buy expensive gaskets again.
 

Latest posts

Back
Top