Rebuilt lower unit really tight, also pinion nut binding with clutch dawg???

[BigBassin78]

I just took apart a 1995 V6 lower unit, and did nothing but switch the upper portion of the drive shaft 25" to a 20". I did replace all seals and gaskets. It was easy to turn before i rebuilt it. Now it is relatively tight and there is a little noise even in neutral. The sound goes away if i pull up on the vertical shaft, there seems to be more play than should be on the vertical shaft. In my mind, the way the lower drive shaft sits should not have changed with just the upper drive shaft change. It seems that if I had about an 1/8" shim between the drive shaft bearing housing and the lower unit housing, it would solve the problem, if that makes sense. I think that the pinion nut and/or tip of the lower drive shaft is binding/touching the clutch dawg, there is a very tight clearance between these parts anyway.

I just dont see how it got all messed up when nothing changed inside the lower unit, as far as shims, gears, prop shaft. Am I missing something? I followed the driveshaft install instructions very closely.

PLEASE HELP!!

 

[BigBassin78]

Re: Rebuilt lower unit really tight, also pinion nut binding with clutch dawg???

Is there a possibility that the pinion bearing race was shifted downward? Isnt this bearing what holds the driveshaft up??

 

[BigBassin78]

Re: Rebuilt lower unit really tight, also pinion nut binding with clutch dawg???

Man, no one know lower units around here.?? I would appreciate any help..

 

[OutOfControl]

Re: Rebuilt lower unit really tight, also pinion nut binding with clutch dawg???

BigBass, did you rebuild the waterpump while you had the LU off?
Have you reinstalled the LU and ran the motor yet?
I replaced my waterpump and bearing seals yesterday and the driveshaft was very hard to turn, I am assuming due to the tightness of the new impeller. It seems to be fine now that I have bolted it back up and ran it up to temperature.
Be patient, someone with more in depth knowledge will answer.
OutOfControl

 

[Chinewalker]

Re: Rebuilt lower unit really tight, also pinion nut binding with clutch dawg???

Are you sure the pinion gear was properly seated on the tapered splines?

 

[boobie]

Re: Rebuilt lower unit really tight, also pinion nut binding with clutch dawg???

Think about this. When the mtr is running the gears are being pushed away from themselves therefore pushing the d/s up. If you put the same shims back in, you should be okay.