Mercury force leaking oil out of lower prop bolt and water in lower unit

[joshbosh]

After the first time out with brand new gear oil in the lower unit, I noticed some oil leaking out of the lower of the two propeller housing bolts (there is one above the propeller on the housing, and one below, where it is leaking). Concerned that I might have a bad lower unit seal or something, I opened up the gear oil drain plug and a little bit of water and some milky gear oil came out. I pumped a little extra gear oil in thinking if I had a big leak it would be low and it hardly took any before spewing out of the overflow bolt hole.

Should I be concerned here? Clearly not much of the gear oil leaked out since it hardly took any additional and it was just a little bit of water. Is it normal to have leakage out of the lower propeller housing bolt? Could this just be unburnt oil in the fuel from idling? I will note that I always disconnect my fuel line after each time on the water and rev the engine up to burn off any fuel left in the engine.

Any help would be greatly appreciated, thanks!

 

[flyingscott]

Time for the smell test and what are the propeller housing bolts take a pic.

 

[Bondo]

Ayuh,... Welcome Aboard,...... Time to reseal the lower unit,...

It shouldn't leak any oil, nor let any water in,.....

 

[joshbosh]

Interesting; I did the smell test and it doesn't smell like gear oil. I took off the prop and there is some fluid around the recessed area near the prop shaft that is blue so it looks like unburnt oil in the fuel. Doesn't explain water in my gear case though so I guess I'll need to run a pressure test to see how the seals are holding up, right?

 

[joshbosh]

Thanks for the replies by the way. The bolt I was referring to is what attaches the prop shaft to the rest of the lower unit. Looks like it wasn't really leaking from there but dripping down from the recessed area near the outside of the prop shaft.

 

[flyingscott]

A lot of lower unit leaks are bad seals on the fill screws. This happens because the fill screw is on the front of the bullet so when you are running the water gets forced in the lower unit. JMO

 

[joshbosh]

That makes a lot of sense. The only way to know is to pressure with a lower unit fill pump line and a bike pump to test it, correct?