gear box oil leaking

[colin333]

hey guys .. ive got oil leaking from or near my exhaust on my 1988 mercury 9,9 outboard ,, any ideas as to why and how to fix,, ,just got it back from mechanic who did a service ,, gear box seal and new impeller .. ran the motor for 10 mins and notice the oil leak
kind regards
thanks for any suggestions and help

 

[Chris1956]

Smell the stuff that is leaking. If it stinks like rotten eggs, it is gear oil, and you have a leak. A pressure test is the best way to find out where the leak is.

Alternatively, if it smells like oil or gasoline, it is 2 cycle oil and normal.

 

[jimmbo]

Where is the Oil leaking out? Is it actually Gear Oil? Being a 2 stroke, that engine will expel unburnt 2 stroke oil, out the exhaust and often, also thru various drains in the gearcase.
That said, you say you just got it back from a Mechanic who replaced the Water pump, and likely the gearcase seal under the pump. Do you know if he did a Vacuum/Pressure Test on it?

 

[colin333]

Smell the stuff that is leaking. If it stinks like rotten eggs, it is gear oil, and you have a leak. A pressure test is the best way to find out where the leak is.// thank you kindly for your help in replying chris , i will spell it tomorrow as suggested ,,

 

[colin333]

Where is the Oil leaking out? Is it actually Gear Oil? Being a 2 stroke, that engine will expel unburnt 2 stroke oil, out the exhaust and often, also thru various drains in the gearcase.
That said, you say you just got it back from a Mechanic who replaced the Water pump, and likely the gearcase seal under the pump. Do you know if he did a Vacuum/Pressure Test on it?

thanks for your help jim .. its coming out just beside the exhaust . its a brownish colour and to me it looks like fresh oil ,,not 2 stroke oil

 

[colin333]

thanks for your help jim .. its coming out just beside the exhaust . its a brownish colour and to me it looks like fresh oil ,,not 2 stroke oil

ps ... i cant be sure but i dont think the mechanic did a pressure test .

 

[jimmbo]

Does it Stink to high heaven? if so it would be gear oil

 

[QBhoy]

9/10 times it’s 2 stroke oil out exhaust. You’ll soon know if it’s gear oil. It’s horrible stuff and stinks. I’d also suggest that it usually won’t be brown gear oil that’s in the gearbox either. If it’s had the usual quicksilver oil that’s been used.

 

[colin333]

thanks for all the help guys ,, i smelt the oil and it didnt smell like rotten eggs, added a pic ,, not the clearest pic ,,but may help

 

[jimmbo]

Well, if oil is getting out, water should be getting in. Remove the Drain Plug and see what comes out. Water, Oil, or something that looks like Bailey's Irish Creme.