oil on skeg, prop shaft seal?

[OldSkool67]

So I found some oil  running down the skeg this morning when I went to clean out the boat from fishing yesterday. Ive never seen it before on this engine. I popped the lower unit plug and no water was present in the gear oil. My previous experience was that when the prop shaft seal leaked I had water in the lube. I tried to identify using odor but that was no luck either, doesnt smell like fuel and oil or gear lube. I use to have some residue like this on my twin mercs but never on my yamaha.

My thoughts are it is just left over 2 stroke oil but I dont want to ignore it and have a larger problem.

Your thoughts please.

[slvrlng]

Pull your prop and see if you can tell where its coming from. My thought is if it was excess fuel oil mix in that area it would be coming out through the hub on the prop. Hopefully one of the true "motorheads" will wake up soon and chime in!

[RickK]

I see that on my OMC - was told it was unburnt fuel/oil mix.  Maybe from idling too much - got a long idle zone before the ramp?

[OldSkool67]

I was fishing canals all day, it was at idle the whole time.

[gran398]

My 25 horse 3 cyl. Johnson does it every trip.

[fitz73222]

Question answered! Are you on premix or still oil injected?

[OldSkool67]

I premix.

I thought thats what it was, I just have never seen that before on this engine.

Better safe than sorry.

Thanks guys!

[fitz73222]

Hey Oldskool,

I've been using one of those little motor mate measuring devices for 35 years on premix engines without any issues and I seem to get consistent ratios. Technically @50-1 it is 2.6 oz per gallon of fuel. But many people round up to 3 oz because it's easier to measure but when you do multiple fill ups you wind up with an aggregate over oiled condition and she winds up smoking like a '57 Johnson 35!

[OldSkool67]

Just a little update, I ran that tank out empty and refueled the boat. Since then it has not had any oil on the skeg. I did start using one of the motor mate measuring devices on this tank of fuel. Might have been just a build up of excess oil at the bottom of that tank.


Thanks for the help guys! Now on to solve my charging issues!