Re: Exhaust Riser gasket change
 

Fund Razor,

I am leaning toward some sealer also. When I seperated my old manifolds/risers, it looked like there was no seal at all. My main concern is isolating the center gasket between the manifold and the riser. Major potential for electrolysis. If I could get a ground wire on the gasket, problem solved.

Re: Exhaust Riser gasket change
 

Mcollinstn says to use "Perma Tex Copper Spray A Gasket."

So that's what I'm a gonna do. :D

Re: Exhaust Riser gasket change
 

I Have Aluminum Manifolds And Risers And Use A High Heat Silicon. It Is A Copper Color, I'll See If I Can Find The Name It Works Great.

Re: Exhaust Riser gasket change
 

I have cast iron manifolds and risers, and I'm gonna use Perma Tex Copper Spray a Gasket, just like Mcollinstn said to use.
He said that it was "magic."

How can you beat Magic?

I have the can sitting on the counter at home. :D

Re: Exhaust Riser gasket change
 

On the blue gaskets, I've used sealer (usually OMC gasket compound). On the gray gaskets no.
No matter which one I've used, I always cleaned the gasket surfaces with a scotchbrite roloc pad on an angle die grinder. Then I use a straight edge to check the flatness of the gasket surface.

Re: Exhaust Riser gasket change
 

I'm using the grey gaskets.

Sounds like I will be extra safe. The stuff that I mentioned is designed for high heat and even heat distribution, also... helps fill microscopic voids.

Do you mean that you cleaned the manifold and riser mating surfaces with a scotchbrite pad? Or do you really mean the gasket?

Then you use a straightedge on the elbow and manifold surfaces? Or on the gasket?

Re: Exhaust Riser gasket change
 

Took them off the boat this weekend and opened them up.

Nasty.

Maybe 45% blocked and rust city.

Looking into replacing the manifolds and the risers x 4 each.

Re: Exhaust Riser gasket change
 

And I believe the winner is Dennis Moore reproductions.

Re: Exhaust Riser gasket change
 

I clean the manifold, and riser gasket surfaces. Not the gasket.
I'm considering replacing my manifolds and risers as well.
I'm looking into the GLM parts. It looks like Dennis Moore is selling them on Ebay. I've heard good things, and bad about them. Have you heard anything?

Re: Exhaust Riser gasket change
 

I hadn't heard anything bad yet.

I was thinking brand new repros would be better than 21 year old rusticles.

What I like about Dennis is that you call him and he picks up.
Hard to find human beings who answer the phone.

I think I am gonna pull the trigger on two sets right now.

Genuine OMC is 1216.00 an engine.

Napa is 1100.00 an engine.

Osco is 608.00 an engine.

GLM is 369.00 an engine.

Will they last 21 years like my OMCs did? probably not.

Will they last the rest of the time I own the boat?
Probably.