50hp Johnson Lower Unit Rebuild

walt501

Cadet
Joined
Sep 9, 2005
Messages
6
Hello all, I posted earlier about rebuilding my worn lower unit. I received a parts manual and a service manual for my motor, but after reading the service manual I have some reservations about tackling the lower unit overhaul myself. The manual mentions several special OMC tools that I don't have, and I'm guessing they would be hard to come by. Given I don't have the service tools, what are my chances of successfully rebuilding this lower unit myself? How do I reassemble everything without those tools?<br /><br />Appreciate your help!
 

wilde1j

Vice Admiral
Joined
Apr 15, 2002
Messages
5,964
Re: 50hp Johnson Lower Unit Rebuild

If you've never rebuilt a LU, you may be ahead having a dealer do it. You need a tool (puller) to remove the bearing carrier, one to hold the driveshaft (may be made from an old crankshaft bottom end welded to a socket) to remove the pinion nut and a shim tool. Most everything else is common shop tools. Since you'll have it all apart, the LU seals should also be replaced at the same time. You'll need a pressure tester to check the LU after assembly. Again, if you've never done it before, I would suggest a shop do the work.
 

ob15

Chief Petty Officer
Joined
Jan 4, 2004
Messages
514
Re: 50hp Johnson Lower Unit Rebuild

I would say you could do it with the help of a shop. Removing, shimming, installing the drive shaft & a pressure/vaccum test can be done by the shop. I think the rest can be done by you. I was going to do that with my 89 50hp but didn't have the time so I bought a rebuilt LU.
 

5466JOHN

Cadet
Joined
Aug 14, 2005
Messages
29
Re: 50hp Johnson Lower Unit Rebuild

IF YOUR INTERESTED I HAVE A 1987 JOHNSON 50 HORSE THAT HAD ONE BAD CYLINDER, THE MOTOR RAN GREAT UNTIL THAT. I AM WILLING TO SELL THE WHOLE MOTOR , LESS CARBS, COILS, AND STARTER. MOTOR WOULD HAVE TO BE PICKED UP. MAKE ME AND OFFER . IM NOT LOOKING FOR BIG BUCKS. LAST TIME BOAT WAS OUT WAS 9-01-05.MAKE SURE THIS WILL FIT.
 

ob15

Chief Petty Officer
Joined
Jan 4, 2004
Messages
514
Re: 50hp Johnson Lower Unit Rebuild

I'd probably take advantage of that offer.
 
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