**help** shifting/grinding when in drive! Need to be fixed asap!

hey so i was working on my '91 Alpha One Mercruiser lower gear unit to replace the water pump impeller. everything when smoothly with the water pump, however, when i try connecting the lower unit back to the upper housing i have two problems.

the first problem is that i have trouble putting the drive in all the way. i have to wiggle it around and turn the prop (the lower unit is in forward gear) until it finally goes it. but i feel like it takes more effort than normal to get it in there. other videos make it seem like it should slide right in there. i have to wiggle it a lot and push up pretty hard to get it to finally get in there.

once its in there i have problems when the boat is on and attempting to put it into drive. it hear like a light grinding/slipping of gears and the prop doesn't move. also as a side note is the prop supposed to be able to move freely when the motor is off and its in drive. i know its supposed to lock when it spins the opposite way, but when spinning it toward the direction of the gear you are in it clicks a few times each complete rotation. its like there is resistance back and once you've passed it it goes for a little and starts again.


any idea??!?!?! PLEASE NEED THIS RESOLVED ASAP!!!!!

Re: **help** shifting/grinding when in drive! Need to be fixed asap!

Just answered a very similar problem to this. Have a read here, hope it helps -> http://forums.iboats.com/mercruiser...60-lower-unit-install-616351.html#post4293142

Re: **help** shifting/grinding when in drive! Need to be fixed asap!

thanks really appreciate that! i'll give that a try.

but when i am putting the splines in should they go in very easily? i mean that right away when the splines are aligned should it slide in easily? i felt like i kept having to wiggle it in still.

also, do the splines only have one way that they have to line up or does it not matter?


appreciate the quick responses!

Re: **help** shifting/grinding when in drive! Need to be fixed asap!

Sounds to me like your alignment is out.

Re: **help** shifting/grinding when in drive! Need to be fixed asap!

Silly Seville said:

Sounds to me like your alignment is out.

Click to expand...

He's only doing the gear housing, not the whole drive...

camcorder44 said:

thanks really appreciate that! i'll give that a try.

but when i am putting the splines in should they go in very easily? i mean that right away when the splines are aligned should it slide in easily? i felt like i kept having to wiggle it in still.

also, do the splines only have one way that they have to line up or does it not matter?

Click to expand...

Yes, you do need to wriggle it a little, and no, the splines line up any way you put the gear housing on. Completely symmetrical.

Chris.......

Re: **help** shifting/grinding when in drive! Need to be fixed asap!

thanks chris! i attempted to follow the directions of the link that you pasted for me earlier and it was still having the same issue. i'm starting to think that its just the gear not engaging fully anymore. i was doing some more research on this topic and noticed that some people say that the shifting cable may need to be adjusted. could this potentially fix my issue?

and should i be able to turn the prop clockwise easily and smoothly when its in drive and the boat is off?


thanks for the quick responses its getting close i feel it! lol