I can't get my lower unit back on!!

jthor3277

Petty Officer 2nd Class
Joined
Jul 25, 2009
Messages
104
I am so frustrated with my '89 Merc alpha one lower unit. I can't get it to seat. It feels like it's stuck. I have it in full forward gear. I think it's not getting in the splines but I have tried to turn the prop with no joy. Any tricks?
 

dubs283

Vice Admiral
Joined
Jul 27, 2005
Messages
5,332
Re: I can't get my lower unit back on!!

check to make sure the shift arm on the drive is aligned properly with the fork in the bell housing

both should be straight, fore and aft

with the drive locked in fwd gear, turn the prop counterclockwise, this will align the splines on the shaft with the coupler

a little oil/light grease on the two o-rings closest to the u-joints on the splined shaft helps get them through the gimbal bearing

once you are sure everything is lined up properly and still won't go all the way on, maybe hanging up about an inch from the bell housing, give it the merkick
 

littlebookworm

Chief Petty Officer
Joined
Nov 30, 2007
Messages
574
Re: I can't get my lower unit back on!!

Sometimes the gimbal bearing, which floats, is slightly cocked, making it impossible to line up everything. If you've got an alignment tool (or can borrow one) slide it in and see how everything lines up. If you tap it slightly to the side and it slides in, you're OK. If it doesn't, you may have to realign the engine slightly. Check this site for directions. Whatever you, do, don't force anything. That will onlly make things worse. Good luck. Hy
 

jthor3277

Petty Officer 2nd Class
Joined
Jul 25, 2009
Messages
104
Re: I can't get my lower unit back on!!

Does it matter if the drive is up or down? I have tried both ways and no luck. I don't get it because it came off easily. I have it in full forward , in gear. I thinkit's getting caught on the shift cable cam.
 

ziggy

Admiral
Joined
Jun 30, 2004
Messages
7,473
Re: I can't get my lower unit back on!!

i'm confused. are ya putting the drive back on the bellhousing. or. putting the lower back on the upper...
 

jthor3277

Petty Officer 2nd Class
Joined
Jul 25, 2009
Messages
104
Re: I can't get my lower unit back on!!

I am trying to put the lower on the upper. I guess I need an alignment tool. It came out so easily and I thought it would go right back in. Guess not. I don't want to force anything and make it worse.
 

xltier

Chief Petty Officer
Joined
May 20, 2004
Messages
636
Re: I can't get my lower unit back on!!

I am trying to put the lower on the upper. I guess I need an alignment tool. It came out so easily and I thought it would go right back in. Guess not. I don't want to force anything and make it worse.

u dont need a alignment tool for putting a upper and lower together.only when u pull the complete drive off the bell housing.
 

meesh

Petty Officer 1st Class
Joined
Aug 24, 2008
Messages
256
Re: I can't get my lower unit back on!!

The alignment tool is for the upper where it goes into the gimbal bearing. To put the lower on you do not need this tool. If your shift shafts are lined up then your shaft splines are not and that's what you are fighting.
 

windsors03cobra

Lieutenant Junior Grade
Joined
Feb 22, 2009
Messages
1,191
Re: I can't get my lower unit back on!!

I fought that stupid battle for an hour before I just pulled the upper back off and put the lower and upper together on a bench, the lowers falls right into the upper with the upper upside down.
When I put the drive back on I had to give it the MerKick and it sat right in there, alignment was great it just needed a little persuasion.

MerCruisers=Good runners.
 

jthor3277

Petty Officer 2nd Class
Joined
Jul 25, 2009
Messages
104
Re: I can't get my lower unit back on!!

I have the shift cable turned all the way to the right, clockwise. I do think I am fighting the shift cable. Is there a way to tell it's lined up? Sorry for the stupid question as this is the first time I have ever messed with a merc.
 

ziggy

Admiral
Joined
Jun 30, 2004
Messages
7,473
Re: I can't get my lower unit back on!!

i've had my share of grief putting the lower onto the upper while still on the boat too. i think it's the water tube that i'm always fighting. best thing i've done to cure that was to read the s/m very close and discovered that if ya follow the instructions to put the water pipe in the waterpocket cover + the guide tube in the waterpump housing. then i have much better success when reistalling. taking the drive off and putting the two together on the bench is the way to go though. much easier that way for sure. now onto your new problem.
I have the shift cable turned all the way to the right, clockwise.
the cable just spins, so i'll assume yer talking about the shift shaft coupler. i assume it's turned to port. the drive needs to be in fwd. this gets the shift shaft coupler facing fwd. also, the helm must be in fwd. this gets that half of the shift shaft coupler facing fwd. too. then your ready to mate them. this is the coupler i'm talking about.
IMG_1516.jpg
that's my 1 drive, your's should be similar. in this pic the helm is in neu. you can see that the coupler is facing some to port. if it were in fwd. that coupler would be facing fwd. if in rev. it'd be further yet to port. when if fwd. the coupler being fwd. it'll allow you to slide your drive on.
have you got the oem service manual for your rig. it's a real big help to have one if not.
 

bigskiohio

Master Chief Petty Officer
Joined
May 3, 2008
Messages
882
Re: I can't get my lower unit back on!!

both those pieces have to be straight bbecause you cant slide the together sideways. same as putting your shoes on ,foot straight ,shoe straight.sorry i thought you had the two halves together ,put i on a bench
 

hoot

Chief Petty Officer
Joined
Sep 8, 2002
Messages
434
Re: I can't get my lower unit back on!!

to second the advice, it can be easier to pull the upper and assemble the two units together on a bench where you can see what is lining up inside then put the assembly back on. the water tube, splines, and shifter tabs have to all fit. and the small o-ring on the side of the lower unit has to stay in place. make sure the o-ring on the drive shaft doesn't come off in the female end of the upper drive shaft as you fight the thing. the splines may be out of alignment enough to keep the units from going together. you can turn the prop a little counterclockwise to see if they will slide on easier.
 

ShaneCarroll

Chief Petty Officer
Joined
Feb 10, 2009
Messages
639
Re: I can't get my lower unit back on!!

I had this issue, and the cause was actually pretty simple, and made me feel pretty dumb. The water intake hose in the upper unit that goes to the impeller was off center a little bit, and it prevented me from pushing the drive all the way up. I had to push that piece of plastic tube up a bit, and then the lower unit went right on.
 

jthor3277

Petty Officer 2nd Class
Joined
Jul 25, 2009
Messages
104
Re: I can't get my lower unit back on!!

Well it turns out I was fighting the shift cable. Ahh! Thanks ziggy and dubs. After I fixed that, a little prop turn counter clockwise and bamn...right in. Thanks for all the help guys. Lesson learned.
 

DrEvil

Seaman Apprentice
Joined
Jun 27, 2007
Messages
43
Re: I can't get my lower unit back on!!

I had the same problem after an impeller change... I had it in forward gear and pushed up enough to get a couple nuts on there (Barley) then I removed it from forward gear into neutral and it popped right in place. Everything went back together fine and she now runs cool :cool:
 
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