LU Inlet Holes Filled

[chadbenton]

I have an 88 150XR2 that I have been chasin an overheating problem on for over 6 years now. I removed my lower unit for another waterpump. I noticed a glob of something in the water inlet area inside the cavity. I knocked it off with a screwdriver and pulled it out, it was a peice of bondo. It was taking up maybe 1/6 to 1/5 of the area, possible water restriction? Only a test run will tell. But, the bondo I noticed was used to fill two upper inlet holes that are'nt used. Could this possibly have been factory, or the previous owner/mechanic.. Should I drill out the holes to allow more water flow? Any thoughts?

 

[cr2k]

Re: LU Inlet Holes Filled

A lot of the bass boat guys or wanna be racers will raise the engine to get some of the prop out of the water. When they do this they have to fill the upper holes to eliminate sucking air. If your engine is mounted at the right depth (bottom of anti vent plate even with keel) you should drill out the other holes and clean out the bondo. You can never have too much water flow (unless you are running in ice water with no thermostat).

 

[Faztbullet]

Re: LU Inlet Holes Filled

Depends on what type boat you have and if it has a jackplate. I have plugged as many as 4 on each side and never had any cooling problems but I use a set screw and Devcon over them. Its possible the bondo was areating the incoming water to impeller,you would have pressure but no volume...

 

[chadbenton]

Re: LU Inlet Holes Filled

Ok, it 18 degrees here, but could'nt resist. Went out to the shop and cleared out the holes. Cant' wait to see how she runs now. I don't have a jack plate and have it set below the keel. I do agree that it could areate the water, the glob stuck out over half and inch. Thanks for the info, just needs to warm up so I can give it a try.........