Lower unit driveshaft not spinning smoothly??

Joined
Apr 22, 2009
Messages
1
I have a 1998 90hp cross flow outboard with the lower unit removed for water pump replacement, and I noticed that when I spin the drive shaft by hand (clockwise), it feels weird...i can hear and feel it almost ratcheting ... i.e. not spinning buttery smooth. It spins easy otherwise, but not what I expected.

It's smoother when I lift slightly, but never completely smooth. This happens in F, R, and neutral. There is about a 1/16th to 1/8th inch vertical play with the shaft.

The prop shaft spins buttery smooth in neutral, but when in gear and I spin the prop shaft, I can hear & feel the same "symptom".

I have had no problem with it in the water to date, and other than having to use controlled force removing the seized impeller, I haven't done anything to damage it. FWIW, it passed pressure and vacuum test and the fluid looked good.

There is noticeable side to side wiggle or movement of the drive shaft with the water pump removed, but I have read that's normal.

the manual I have has no specs or end play tolerances or description of how it should spin, so I have no idea if this is normal or if I have a problem. I also can't remember testing it when I first removed it before dis assembly of the water pump, so I really have nothing to compare to. :(

Any ideas??

Joe
 

gsyfishy

Petty Officer 2nd Class
Joined
Apr 25, 2008
Messages
173
Re: Lower unit driveshaft not spinning smoothly??

Is it doing this ALWAYS when you manually pull or push the shiftrod to put in gear? I believe the linkage from the shifter is set up to move (up/down) just enough to put it in gear, when we pull it up or push it down manually we go too far, or not far enough. Try and move it just enough to get it into gear, and then back to neutral and see if it still grinds.
 
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