What to do with this motor

[Rizzo]

Took my 1980's merc 15 hp to a local marina (which will remain nameless for now...I bet Brian could guess)2 years ago for a tune-up. Motor ran fine that season but at the end of the year as I drained the oil from the lower end I noticed water had gotten in, and that the upper screw came out real easily (ie housing stripped). After changing the oil I put the screw back in place and siliconed over it. This past season the motor ran fine again, but in the fall while changing the oil I noticed water had gotten in again. Marinas tell me to change the lower unit housing at a cost of around $500 - not gonna happen on a motor that's over 20 years old. Any suggestions? Anyone want to buy it and tinker with it themselves shoot me a pm!.

[Bill Shearer]

This should be a pretty easy fix for that

 

http://www.emhart.com/brands/heli-coil

[DanD]

If there’s room; I wouldn’t even bother with a heli-coil; plus the wall thickness of the lower unit may not be thick enough to hold a heli-coil? Get a threading tap and a replacement bolt/screw, one or two sizes larger in diameter. Tap new threads in the stripped out hole and stick the replacement bolt in; along with a sealing washer.

After that I would have the lower end pressure tested to confirm that there are no other leaks allowing water in.

 

Dan.

[grt1]

yup I would also try to rethread with a larger bolt, but then again i'm not a mechanic.

[Fisherman]

Have you had a pressure test done? Cold be as simple as one of the 3 gasket sets gone south, 1. in front of the prop, 2. impellor gasket, 3. Shift rod seal. If any of those three leak, then you may as well ram some toothpicks in the upper screw hole.

[Uncle Buck]

If its a longshaft, I'm interested

[Rizzo]

thanks for the input guys, U B I sent you a pm

[camillj]

Fix the rubber before you start messing with the metal ... much more likely that one of the screws needs a new rubber washer than a thread issue.