84 MR - Substitute Tool For Replacing Lower Shift Shaft Bushing?

[andyandy]

84 mercruiser MR outdrive. My lower shift shaft bushing (oil seal) is leaking slightly, especially when it's hot and the sun beats down on the outdrive. The drive oil drips out of the lower weep hole. I can see oil seepage around the bushing and down in the cavity so I want to service it while doing the water pump. The drive held 15 PSI pressure for several hours when I pressure tested it before separating the unit.

Is there a technique or home made tool that can be used to remove and replace the bushing?
The specialty tool merc 91-31107T runs $16-$24, and I will buy it if absolutely necessary.

Also, is ot OK to replace just the oil seal? or should the whole bushing assembly be replaced?

Thanks

Andy

 

[Eric 3.7LX Alpha 1]

Re: 84 MR - Substitute Tool For Replacing Lower Shift Shaft Bushing?

In the sticky at the beginning of this forum there is a link to homemade tools:
http://forums.iboats.com/showthread.php?t=470339

 

[andyandy]

Re: 84 MR - Substitute Tool For Replacing Lower Shift Shaft Bushing?

Thanks for the tip. I bought one of these at a local Pep Boys automotive parts today and it lasted about 2 minutes. It was a cheap cast tool made in (gues where? it starts with a 'C' and ends in 'hina'). :facepalm: I suspect it MAY have done fine to retract a rear break caliper but not to loosen my 84 MR bushing. The fit was good but the cast piece could not withstand the torque. Oh well, live and learn. Most of the home made and alternative tools are truly worthy but i just got a cheap tool. So back to Pep Boys it goes and I'll buy the proper tool to do the job.
Andy

 

[achris]

Re: 84 MR - Substitute Tool For Replacing Lower Shift Shaft Bushing?

....

Also, is ot OK to replace just the oil seal? or should the whole bushing assembly be replaced?

Thanks

Andy

If the bushing is ok, then yes, replace the seal in it... But, at that age, I would be surprised if it's reusable...

Chris...

 

[andyandy]

Re: 84 MR - Substitute Tool For Replacing Lower Shift Shaft Bushing?

I bought a new bushig and the right tool which fits perfectly. But moderate pressure with a 1/2 inch socket wrench stripped the bushing. Now what? Not sure why this bushing is in so tioght.
Sprayed some PB Blaster on it and trying to figure out a strategy for removal. Impact wrench? dremel new slots?
How to get this bushing out once the slots are stripped?

 

[UNSUREBOATGUY]

Re: 84 MR - Substitute Tool For Replacing Lower Shift Shaft Bushing?

I had the exact same experience when I replaced mine (right tool, stripped bushing, etc.-very stuck). I ended up having good luck pounding the bushing loose with a big flathead screw driver and hammer. Just need to be careful with the angles and placement of the screw driver so as not to damage the case or shift shaft, etc. The screwdriver dug into the softer aluminum to get a good grip, but it still didn't start moving at first because it was so corroded to the case. Eventually the bushing actually cracked, but broke free and turned out. I cleaned everything up and installed the new one with a little grease so it might be a little easier to remove years down the road. I'm no expert, but I was very careful not to damage anything and it worked out well in a seemingly bad situation. Just a thought. Good luck.

 

[andyandy]

Re: 84 MR - Substitute Tool For Replacing Lower Shift Shaft Bushing?

That worked. Big screwdriver and hammer to the rescue. At first, half of the bushing tore off without the threads budging, but then the second half turned and i got it off. Thanks for the tip.