115 Lower unit Bearing

[jd438]

I have a 1985 115 hp Merc inline 6. I took the lower unit off the other day to put in a new water pump. While doing this I noticed that with the water pump off the drive shaft had some play in it. Is this normal? Should I replace the top bearing that I could see with the water pump off? Can this be replaced by removing the water pump again?

 

[Chris1956]

Re: 115 Lower unit Bearing

Some of the top driveshaft bearings were only shimmed properly when the LU was installed. Also, over the years merc had changed the installation of the upper Driveshaft bearing. A service manual for your exact motor will tell the tale.

Some motors had spring loaded pin in end of driveshaft to shim bearing. Some LUs (Alpha I for sure) had cone bearings installed small end up.