Burnt oil or gearlube coming from exhaust and prop??

[swen2bry]

1995 Mercury outboard SN# OG252302 40hp

Mechanic said it is jusy unburnt oil and some power tune. I am worried that I have bad seals and that my gearlube is leaking. It does this after running for hours everytime out of the water and sometimes in much larger volumes...any suggestions??

 

[Bob_VT]

Does seen like allot! Remove the top plug for the gearlube and the level should be right up to the bottom of the threads. If you use a q-tip you can ip it into the oil and check the color. It should be blue/green and not milky.

But yea the 2 strokes ALWAYS have a seepage of oil from the exhaust

 

[swen2bry]

Okay I unscrewed the vent and dabbed the qtip in it and it was indeed a transparent bluish green color. So that would confirm that fluid is just unburnt oil and powertune? Boat sat for 7 years I had a bunch of work done to it. Carbs, fuel lines, filters, gear lube, powertune..

 

[kmarine]

Your carb may need adjustment seem to be running rich. A pressure test is the best way to insure oil is not from outdrive.

 

[swen2bry]

When you say out drive is that the lower unit and how would I do a pressure test?

 

[Chris1956]

Sniff the oil. If it stinks like rotten eggs it is gearoil. If it smells like regular oil or like gasoline, it is unburnt 2 cycle oil or residue from decarbonization, and is not an issue. No need to pressure test unless it is gear oil.