I have the later plastic impeller housing with the smaller 0763735 impeller. I looked at Marine Engine for the gasket which is 0324901 shown in the parts for a 1979 6 hp that uses the plastic housing. The '79 parts listing states it takes 2 gaskets, but only shows one between the housing and the impeller plate in the exploded diagram. As i recall when i did a 6 hp with a plastic housing the past,i used 2 gaskets on both sides of the impeller plate.
The '66 6602 i'm working on now had just one gasket when i got it,placed between the housing and the plate as it should be.. It had some kind of gasket sealer between the bottom of the plate and the bearing housing.
I would prefer to use 2 gaskets,especially if the bearing housing is pitted., but thought i would ask for opinions after i saw the discrepancy on the number of gaskets used.
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