Mystery O-Ring

[ezmobee]

Last night I removed the lower unit from my '73 Johnson 85 to do an impeller change. When I dropped the LU an O-ring fell out onto the floor. It is about the size of a quarter and still in good shape. I have no idea where this goes. Any ideas?

 

[steelespike]

Re: Mystery O-Ring

I believe there is an oring that goes around the drive shaft to seal the spline where it goes into the crank.You should put a thin coat of grease on the spline to keep it from seizing to the crank.Just a thin coat as too much will keep the spline from sliding into the crank.