Leaking oil from water pump weep hole 1960 Johnson 18hp Seahorse

[Zapit2um]

I have a 1960 Johnson 18hp Seahorse and have replaced the lower unit with one I took off of a 1959 model. I also rebuilt the carb and while I was trying to get it running, which I did but was running rough and kept on dying on me, I noticed a bunch of oil in the tank of water I had the motor sitting in. Looked like an oil slick on top of the water. I pulled the motor out and noticed that I had oil leaking from the waterpump weep hole. Any idea where this oil is coming from? The attached pic shows the location where the oil is coming from, the pic is from the lower unit I pulled off the 1960.



Yellow arrow is location of leak.

 

[Will Bark]

Re: Leaking oil from water pump weep hole 1960 Johnson 18hp Seahorse

Probably nothing more than unburned oil/gas leaking out and is normal; in the lake you wouldn't see it but will in a tub.

 

[Zapit2um]

Re: Leaking oil from water pump weep hole 1960 Johnson 18hp Seahorse

That's what I thought as well, but there seems to be a lot more this time than the last time I ran it in this tank. And whan I pull it out of the tank the lower unit is just covered with it. Perhaps I'm not getting a good spark or there is no spark on one of the cylinders, it was running rough) causing a great deal more of unburned fule than would typically be present.

 

[Chinewalker]

Re: Leaking oil from water pump weep hole 1960 Johnson 18hp Seahorse

Some unburned fuel is normal. Lots may indicate a misfire. Some investigation is in order. Compression readings? Spark test under load?