Oil Dripping from lower unit

[dblanton]

1981 75 hp Evinrude has some two stroke oil from the fuel oil mix dripping from the lower unit at the prop, no fuel just oil. I checked the gearcase oil, no signs of water in the gearcase and the gearcase was full so I'm sure that the dripping oil is not from the gearcase.The oil is much to thin to be gearcase oil. Where is the oil comming from?

[Frosty]

Thers another thread on the forum with a similar problem -- he also had fuel leak from his power head.

I think yours is similar in so much as it is normal for exess fuel around the carbs from reversion etc to run down the leg when switched off. the fuel/oil mix will evaporate leaving a thin oil.

In the old days we would disconnect the fuel pipe from the engine and let her run out of fuel. They dont do that any more. Just switch off and hit the trim button!!!

Personally if you dont have an obvious fuel leak and the gearcase is full I wouldnt worry too much about it.

But to answer your question its probably fuel oil.

[dblanton]

I got the leaking fuel from the power head fixed by resealing the crankcase halves. The oil dripping from the lower unit where the exhaust comes out is a new issue.
It's definitely oil from the fuel/oil mix, not oil from the lower unit gear case. The oil is black and has an exhaust smell to it. The oil in the gear case is almost as clean looking as it was the day it was put in.
Engine seems to be running fine. Other than the nasty mess that the dripping oil leaves on my garage floor should I be concerned? Is it normal for an engine to do this, if so what would be the expected normal amount of oil dripping out.

[redtech]

sounds like you fuel/oil mix is to heavy on the oil if your in question of anything else your carbs may to to rich

[razbarb]

I've noticed the same thing on my 30 johnson.
Without knowing why, I assumed it was excess fuel leaking out.
My fuel mix was a little heavy on oil - 500ml to 22.5l.
I also noticed a dark smear down the leg from the two holes at the back of the leg, which I attributed to my rich fuel mix.
The motor has just been tuned and serviced.

[redtech]

if the motor has just been tuned and serviced the asuming the tech did chech everything then again i'm going to look at the oil fuel mix it is often thought that a little rich or heavy can't hurt but to methat means someone is coming back with a complaint. liten up on the mix a little and give the engine a good hard run see if this ends the black goo comingfrom the lower

[Frosty]

I would strongly recomend you do not experiment with fuel oil mix and then give the engine a good hard run.

If you wish to eliminate your suspicion of a strong mix then drain the tank and refill with the proper mix for your engine.

Fuel will evaporate from the mix leaving the oil. If this is questioned put some in a bowl and put it outside in the sun.

The reason why it is black and gooy is because it has just run down the inside of the exhaust trumpet and or leg.

It will eventually come out of the bottom of the engine by the water pump.

Look at the back of a 2 stroke motorcycle. There is black gooy oil coming from the exhaust --it is 2 stroke and is lubricated by mixing oil with fuel.

Some oil will be passed unburnt into the exhaust.

If 2 strokes were clean engines we wouldnt have such a fuss over the banning of them.