How do I keep my crusader exhaust risers from leaking?

[imported_ironmike]

Greetings,
I'd like to tap into the forums vast expertise. I have a crusader fresh water exhaust setup with the 8" style log risers and 3" elbows installed on 2 Chevy small blocks. The risers bolt to the exhaust manifolds using 9"studs, bolts and copper washers. It's my understanding that the copper washers keep the risers from leaking at the place where the risers bolt to the manifolds. This is the raw water side since the block off plates/gaskets provides a good seal from anti-freeze leaking. I have rebuilt two sets of engines and replaced the exhaust but haven't had good luck in keeping the risers from leaking. I was looking for a little insight on this. I've tried doubling the washers but it still leaks enough water to cause corrosion. I also suspect that the copper washers cannot be reused? Also, l do install with anti-seize compound since if this is not used, it's almost impossible to separate the risers from the manifolds. Thanks in advance.

 

[Scott Danforth]

New risers, manifolds and elbows? If so, a large flat file to true up the mating surfaces

 

[GA_Boater]

The copper washers aren't washers. They are more like copper gaskets and probably have a steel washer between the copper and nut. They can be reused by annealing. Use a propane torch to heat the copper until it's red hot and let it cool. Annealing softens the cooper so it conforms to an irregular surface. A little sealant wouldn't hurt.

Only use the anti-sieze on the threads, it isn't much of a sealer.

 

[imported_ironmike]

I forgot to mention that I did try using steel washers between the bolts and the copper washers. I will try heating the washers and placing some sealant on them.
Thanks.

 

[Bondo]

Ayuh,.... Where, Exactly is the leak,..??