Gear Oil Leak - 1983 Mercury 7.5 hp 2-Stroke

[BurnleyCrew]

I just cleaned up and serviced our family 7.5 hp 1983 Mercury 2-stroke short shaft (don't think a 4-stroke was an option then) and it runs great with the exception of water getting into the gear oil. I ran it for about 10 minutes (in a large garbage can) in both neutral and forward and then drained the new gear oil that I had replaced an hour earlier and it was very milky.

A couple of questions. As this is an old motor and not worth getting fixed at a shop I want to do any repairs myself. Where is the water most likely getting in? Also, what is involves in repairing this problem?

Any advice would be great as this motor has a lot of memories attached to it!

Ian

 

[fisherguy123]

Re: Gear Oil Leak - 1983 Mercury 7.5 hp 2-Stroke

I bought an 82 merc and found the gear oil milky as well......I changed the small gaskets on the screws and haven`t had any water since . This would be the cheapest first step to try...maybe you could be so lucky as I was......good luck !

 

[Mi duckdown]

Re: Gear Oil Leak - 1983 Mercury 7.5 hp 2-Stroke

Serial number?
Don't think it is a 4 stoke.
as fisherguy mentioned. It could be as easy as the vent and fill gaskets/washers.
Impellar change is a must.

 

[bull705]

Re: Gear Oil Leak - 1983 Mercury 7.5 hp 2-Stroke

I've got the same problem but mine is a mid 70's. I changed the seals on the fill screws but still have a problem...did you manage to fix yours?