80’s evinrude 15hp leaking oil

[Robins36]

Hello all, I’ve been getting my stuff ready for fishing open water and when I pulled my motor out of storage, there looks to be oil coming out of the water drain hole in the bottom of the leg. The motor is a 1986 evinrude 15 hp. When I started it up in the rain barrel, some oil leaked out into the water. Does anyone have some knowledge as to what could be causing this? I’ve got to get this fixed up or I will be stuck using the Minn Kota as I can’t put this motor in any lakes like this. The motor was in for service about 5 years ago to clean the carburetor and tune up.

Thanks in advance!

Daryl

[gunluvr]

If you didn't keep your motor in warm storage for the winter, a small amount of water in the lower leg froze, expanded, and pushed out the oil seal in front of the prop, or worse, cracked the housing.

[calgarygringo]

As said potential seal gone and needs to be replaced. I have a 78 model and did all the lower seals a couple years ago when I did the prop seal and was a pretty easy Saturday afternoon job. Could have been water could be just old age and the seals are drying out and shrinking causing leakage. First step is to determine exactly where the oil is coming out and if just a prop shaft seal they are only a few bucks and easy replace or as I mention at that age just do them all if you are handy and be done with it.

[ccmckee]

Hopefully just the prop shaft seal as mentioned, pretty straight forward job. A lot of times you can pick up fishing and it will get wound up in the seal.

[Headdamage]

If it is gear oil it is as stated above, however I have seen oily 2 stroke buildup in the exhaust of these motors and this can seep out over winter make it look like a leak (it will be black).

[Robins36]

Thanks all! The prop seal sounds right... we got some fishing line tangled up in the prop shaft there late last year with all the kids fishing with me. Hopefully i can get some parts next week and get it ready.

Greatly appreciate all your help!

[Penner]

Originally Posted by Headdamage

If it is gear oil it is as stated above, however I have seen oily 2 stroke buildup in the exhaust of these motors and this can seep out over winter make it look like a leak (it will be black).

It could be the above. The OMC 2-strokes are notorious for having exhaust build-up seep out quite regularly. If its black or brown this is what it is. If it is light yellow/green its gear case oil then the likely the prop shaft seal. Un-burnt oil/fuel will show-up in the water when using the motor quite regularly. Those old 2-strokes are bullet proof reliable but they are not the cleanest nor efficient operating units that is for certain.

A guy should always change out the gear case oil in the fall before putting the motor away for storage. This ensures no water is in bottom leg to freeze up. When changing gear case oil in bottom leg, always let changed oil sit for a hour to see if any water settles to the top. If water appears, you have a blown seal somewhere than needs to be replaced.

[TimeOff]

Originally Posted by Penner

It could be the above. The OMC 2-strokes are notorious for having exhaust build-up seep out quite regularly. If its black or brown this is what it is. If it is light yellow/green its gear case oil then the likely the prop shaft seal. Un-burnt oil/fuel will show-up in the water when using the motor quite regularly. Those old 2-strokes are bullet proof reliable but they are not the cleanest nor efficient operating units that is for certain.

A guy should always change out the gear case oil in the fall before putting the motor away for storage. This ensures no water is in bottom leg to freeze up. When changing gear case oil in bottom leg, always let changed oil sit for a hour to see if any water settles to the top. If water appears, you have a blown seal somewhere than needs to be replaced.

What Penner said. Also if you haven't changed out you're water pump in a while, you should consider doing that as well. Good practice to do it every couple of seasons, at around $50 for a pump kit, it's cheap insurance. It gives you a chance to grease the splines on top of the driveshaft where it engages the power head as well. Seen those so rusted that you can barely get the gear case off on motors of that vintage that have never had their water pump replaces

[bat119]

Princess auto sells an outboard gear case filling pump kit makes changing oil easy, comes with adapters to screw in the bottom plug then pump the fluid in.
I change mine at the end of every season mostly to check for leaks if enough water gets in the casing could crack over the winter.