Merc. closed cooling block off gasket or plate?

[cookiesareyummy]

Mercruiser 5.0L closed cooling. 1995 I think.
I am changing the manifolds and risers. The riser gasket on the old risers was just a block off gasket. Someone said I should use two gaskets and a stainless steel plate between them. I'm just curious why I would want to do that instead of just using a block off gasket like there was.

 

[Don S]

Re: Merc. closed cooling block off gasket or plate?

No need to anymore. Two gaskets and a SS plate is how they blocked them off in the early years. Then new blockoff gasket has a thin SS plate made inside it.

 

[cookiesareyummy]

Re: Merc. closed cooling block off gasket or plate?

ok cool, thank you.