Oil leak from behind prop Evinrude 60HP 1990

[Clearsky]

After about 4 weeks sitting with engine fully down I noticed a small amount of oil seeping from behind the prop. The oil is pitch black, and only a few drops have come out, nothing came out for the 1st 3 weeks of sitting with engine down. I have checked the oil in the gearcase and it was clear and was still full. I have run the engine on muffs a couple of times in the 4 weeks. Could the oil just be exhaust residue? or is it likely to be a seal behind the prop.<br /><br />Just one more thing, is it recommeneded to leave engine down or up when not in use for long periods? I put it down as I was thinking it would relieve from pressure from the transom and the tilt and trim, but I'm only guessing.<br /><br />Any advice would be great.<br /><br />Thanks

 

[ob]

Re: Oil leak from behind prop Evinrude 60HP 1990

It's just exhaust residue.No big woop.If the exhaust housing however is collecting this residue regularly,it is indicative of the engine being in need of a decarb.Might also insure that 60 hp engine is propped to turn 5500-6000 at wide open throttle as well.Overpropping causes coking of cylinders as well.Lots of slow speed trolling loads them up too.

 

[Clearsky]

Re: Oil leak from behind prop Evinrude 60HP 1990

Thanks OB,<br /><br />I should have mentioned, I'm running a 25 to 1 fuel to oil mix at present as engine is being run in after a rebuild, I would imagine this fuel mix could add to the problem.

 

[ob]

Re: Oil leak from behind prop Evinrude 60HP 1990

Absolutely.Get throught the break-in and see if she clears up.Anyway,make sure that engine as propped will rap out to the rpms I mentioned above or you'll be doing another overhaul sooner than expected.

 

[Clearsky]

Re: Oil leak from behind prop Evinrude 60HP 1990

Thanks again OB,<br /><br />Were just coming into winter here in aus, but next time I take her out I'll check that I can get the 5500-6000. I have only had the boat for a couple of months, I know I've had it up to 5000RPM but not sure if this was WOT, I think there was bit more in her, but I'll double check it.

 

[ob]

Re: Oil leak from behind prop Evinrude 60HP 1990

Cheers and happy boating.