Need help identifying gear (?) oil leak - 10 HP 1961

[taki]

I recently got a 1961 10 HP Sportwin - this thing is great. It's been idle for a few years, so I replaced the impeller, drained the gear lube, got new plugs and tank tested.

But, after another longer tank test today, I noticed greenish oil floating in the tank. Upon further inspection, I found two drain holes in the lower unit (or at least I think these are drain holes), and a greenish oil is leaking from them, especially after the motor was raised and lowered again.

I haven't drained the gear oil yet.

Assuming this is the gear oil, where should I look for leaks? I haven't replaced any seals while replacing the impeller. I did put some sealant on the mating surfaces of the water pump and the lower unit.

Could use some help. I'm attaching the pictures. Thank you.

 

[RCO]

Does it have a strong sulphur type smell? If it does it is gear lube. Looks more like unburned 2 stroke oil to me, which is totally normal especially when running in a barrel. Probably the most often asked question when dealing with old outboards.

 

[Rustywrench]

Of its gear lube (you can tell by the smell) then you have the classic shift rod o-ring problem. #301877 will need to be replaced. Check it out on YouTube. Several videos of gearcase rebuilds. You can get your parts right here from Iboats.

 

[taki]

They really need to make the oils in different colors...

I tried to smell the gear oil bottle and whatever stuff is coming out of the holes...I guess this is why I don't understand wines - it all smells like gas to me. Maybe I'll try to smell it again in the morning. Nothing like the smell of gear lube in the mor... nevermind.

I think I'll let it stand and drain the lower to see if there's any water. And will get the O-ring just in case. Any other "just in case" parts should I get while I investigate?

I appreciate the advice and the patience while dealing with newbies.

 

[oldboat1]

Sure you put gear lube in the gearcase (not 2-cycle)? Might check that gear oil bottle again.

 

[taki]

Pretty sure - I bought the TWC3 oil after I filled the lower. Tried sniffing again and compared the color - the gear lube I have is grass green, while the stuff that's leaking is greenish towards slight brown. Also the gear lube smells less strong than the leak, which mainly smells of gas. Could be the unused oil (I'm running 1:24).

We'll see how the gear lube looks tomorrow and if there's water.

 

[racerone]

This is one of the most often discussed subjects / questions.-----Completely normal for that motor.-----Little bit of dish soap and the tank is clean again.----Pressure test the lower unit to test seals.----Just ran a 1963 version and they are a wonderful motor.