OMC 9.9 / 15 impeller housing related questions

[fleetwin]

I don’t recommend following Leeroy’s suggestions about drilling extra holes in that exhaust housing so the water will drain around the taller grommet. The problem here is that if the correct grommet is ever installed during future servicing/repairs, water probably won’t build up in "wall of water area" due to the extra drainage holes. I have never had a problem getting that water tube properly installed in the short grommet, especially if the water tube is original/unmolested with the nice rounded edges.
If you are really intent on using the taller grommet on sealed exhaust tube models, I think it would be better to modify the tall grommet by drilling relief slots in the flared edges where it butts up against the drain holes in the exhaust housing.
Like others have said, be sure that drain hole just above the gearcase bullet is clear! It is probably helpful to enlarge that hole just slightly to help ensure it doesn’t plug up so easily. I kind of doubt the exhaust drool you are seeing is related to drainage of the "inner wall of water", probably related to low engine temp and idle quality. It is usually a good idea to give any engine a good blast at WOT after extended periods to burn off the goo/drool that is likely to build up.

[Alan]

Yeah, I enjoyed Leeroy’s ramblings, too.
But, I’m not going to modify anything, and am glad to know which grommet is correct.
Naw, I didn’t really think the grommet would make much difference in it’s drippiness. Airing it out a bit before shutting down is wise, as it’s often been the trolling motor. I’ll make sure the drain hole is clear, too.
It got me, my wife, and friends off the ocean when the main motor quit, (about three miles) so it will always have a home w’ me!
Again, love this site, and appreciate the community.
Peace!
Alan

[Author]

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