oil leak on 2 stroke leg

[Bob Jack]

My 2 stroke 15 hp Yamaha started to leak oil about 3 years ago.
Why does my 2 stroke 15 hp yamaha leak oil at the prop and leg joint and how can I stop it?

 

[Simi 60]

Gearbox seal
Possibly fishing line
Pull it appart and check it out, pretty easy
Bound to be a YouTube video.

Hopefully after 3 years it's not ruined by any salt water ingress.

 

[ragin cajun]

Is the oil coming from the exhaust port of the prop? if so that is evaporated gasoline/and residual oil left over. Oil does not evaporate therefore runs out of the exhaust. Had a 25hp yamaha the would do the same . Run your carb. dry after using your outboard by disconnecting the fuel hose from your engine. This will keep your carb from getting gummed up with old fuel also.

 

[twistedtree]

And check the oil level in the lower unit…. If it’s been leaking for three years, it could be very low.

 

[Bob Jack]

Is the oil coming from the exhaust port of the prop? if so that is evaporated gasoline/and residual oil left over. Oil does not evaporate therefore runs out of the exhaust. Had a 25hp yamaha the would do the same . Run your carb. dry after using your outboard by disconnecting the fuel hose from your engine. This will keep your carb from getting gummed up with old fuel also.

The black oil seems to be leaking out between where the prop is attached to the outboard leg.
Ps I have tried unplugging the fuel line and running the engine until is stops. - no success.

 

[C lectric]

Pay attention to Post #2 from Simi. Fishing line floating has been the cause of many outboard engines developing oil leaks. Either learn to do the work yourself or get it checked.
If you elect to do it yourself I suggest getting a repair manual and do a bit of study.

Check the oil level soon though as if that is the leaking fluid, failure to deal with it in time will cost you a major repair.

 

[Bob Jack]

There is no fishing line wrapped around the prop union and the oil level in the lower unit is fine. One Mechanic I spoke to said the black oil drip was left over from the burning of the two stoke fuel mix I am runing 100 to 1 (as advised by Yamaha)

 

[Bmarler]

Two strokes want to be run hard in order to stay clean. Pull the plug and look at the color. I bet it’s black and wet looking.
If the motor is undersized and can’t get up to speed it’ll act like that too. You end up lugging it all the time and it never gets up to full rpm.
You might try changing the two stroke oil to see if you can find something cleaner too. Hard to say if that’ll work, but might be worth a try.