L/u on a 1977 mariner wont go all the way in

[Hitnmiss]

I have a 77 mariner 6 cyl 115 that the lower unit is giving me fits .eerything is lineig up water tube,itll go up and still have about a inch left i cant figure it out,oh its another lower unit its a arly 80s .

 

[jimmbo]

Have you tried rotating the flywheel as you are pushing it on? Since you are trying to install a different LU, did you check to see if the splines are the same as the old one?What about the shift shaft?

 

[Hitnmiss]

Yes i have and ive also checkd the shaftand its identical

 

[Chris1956]

The gearcases can be tight. Make sure the driveshaft splines are mated, and the shiftshaft splines are mated and then wiggle it into place. Put a nut on the front stud and tighten with fingers only. Now wiggle until you can thread a nut onto next set of studs and wiggle some more, tightening nuts with fingers only, until the gearcase mates with the midsection.

 

[jimmbo]

Clean the splines and lightly lube them. DO NOT put any grease on the end of the shaft as that can cause problems