1966 20 hp johnson Lower Unit seal

[defiantz]

Frothy white oil sitting on top of water pump housing. I changed driveshaft seal and no change. Replacement seal not as thick as old seal and only a 1 way seal (keeps oil in). Is it possible that the old seal was a 2 way seal (water out and oil in). If so can another seal be installed upside down


thanks

 

[oldcatamount]

Re: 1966 20 hp johnson Lower Unit seal

There are 3 seals in there, prop shaft, drive shaft, and shift rod. "Frothy white oil sitting on top of water pump housing" more than likely means the drive shaft seal is bad. If you have a air pressure test pump, you could see which seal is leaking. I suggest that you change all three. Rule of thumb for a motor of that age, is that, if one seal is bad, so are the others.

 

[defiantz]

Re: 1966 20 hp johnson Lower Unit seal

I have already changed the drive shaft seal and still leaking. That is why i am thinking that the replacement seal should be a two way seal to also keep water out. There is no froth oil anywhere except on drive shaft. I was thinking it might also be an exhaust seal pushing gas-oil mix down shaft but installed another lower unit and no problem

thanks