68 Johnson oil leak?

[uglysteve]

I just finished resealing the lower unit on my 68 Johnson RDS-30 d, 40 hp. There is oil leaking from a hole on the upper case half, highlighted in yellow in the picture.
What is this hole for, and how do I stop the leak? I haven't found anything in the parts diagrams that shows a seal here.
Thanks,
Steve

 

[jimmbo]

Welcome to iboats. No Picture

What color is the oil? Does it stink like gear oil?

 

[uglysteve]

Thanks for the welcome, Jimmbo.
The picture shows up on my computer. I don't know what to do to fix it if it doesn't show up on other computers. I am posting it again.

I bought an old Dura Craft runabout for $300, and have been fixing it up. I just pulled apart the motor and sealed the lower unit, replaced the O-rings in the steering pivot, new impeller and water pump seals. Painted everything Jonson forest green. I thought I had everything leak tight. After running it for a while in a water tank, oil started leaking out of this hole.
Thanks,
Steve

 

[uglysteve]

I just went out and took a sample. It doesn't smell like gear oil, it is gray. It must be from the exhaust. It seems thick like gear oil, but doesn't smell like it. Must be the 2 cycle oil from the exhaust. It has been sitting for many years. It was back firing a lot at first. Started to smooth out after running a while. May be I should put some air in the hole and see where it comes out.
Steve

 

[uglysteve]

I got it figured out. The crankcase drain is dumping oil and it comes out that hole. I found this post that covers a modification to recycle that oil.
http://forums.iboats.com/forum/engi...ing-fuel-efficiency-in-a-big-twin-check-valve
I may do this soon, I don't like the idea of dumping oil in to the lake.
Thanks for the help,
Steve