Re: 1979 90Hp 6cyl lower unit
It can be done without pulling the bearing carrier if you're extremely careful.
Take a sheet rock screw or equivalent thin, sharp sheet metal screw. I like the sheet rock screws because they're hardened with very sharp tip.
Give a small rap to the screw and the tip should puncture the old seal. After that you should be able to screw it in and get enough purchase to be able to pull out the old seal.
You must use extreme caution to avoid scratching the propshaft surface, otherwise it'll probably leak afterwards.
Also be mindful the propshaft needle bearing is right there fwd of the inner seal, you don't want to run the screw into the bearing either!!
Once you get the old seals out, clean & degrease the seal area. Apply a very thin coating of Loctite blue or red on the outer diameter of the seal. Drive it in with a suitable pvc or steel tube, sized to just barely fit the O.D. of the bearing carrier seal area.
Note that each seal has its own orientation; the first one is driven in with the lips of the seal facing towards the oil-containing part of the gearcase (so you're driving this one in with the flat face of the seal facing you); the last seal is driven in with the lips facing to the water-side; thus you'll be looking at the lips of the seal as you're driving it in.
If you can get the seals out using the above technique, all's the better. Failing that, of course you're gonna have to pull the bearing carrier.
You'll need to make or purchase the special tool to remove the gearcase locking ring. If your motor is a Salty Dog, it's also going to take a judicious application of heat around the gearcase to expand the gearcase and help loosen up the locking ring (which has normal right-handed threads, BTW). Penetrant such as PB-Blaster will help loosen the ring up.
In extreme cases you may have to carefully drill the ring out and break the pieces of the ring to remove them.
Note there are lock tabs which will be bent up into the slots of the locking ring; you have to pry these out with a small screwdriver then tap them flat, or you won't be able to turn the ring.
Once the gearcase locking ring is removed, you can use a slide hammer attached to the end of the propshaft to coax the bearing carrier out of the gearcase. After that, the carrier slides right off the propshaft and seal R&R is a simple matter.
Note that the shift plunger is slip-fitted into the end of the propshaft, make sure it stays in the end! Hold it in place with a bit of grease if necessary, you don't want it falling out upon installation.
Note there is an O-ring on the bearing carrier that must be replaced. Clean the I.D. of the gearcase housing where the bearing carrier will sit. Clean any deposits/crud off the O.D. of the bearing carrier before reinstallation.
Spread a thin coating of oil on the new seals' lips. Coat the O.D. of the bearing carrier with Permatex No. 3 non-hardening Aviation-Type gasket dressing. This'll help with any future removal jobs and also prevents salt deposits from building up and potentially cracking the gearcase.
Note there is a key at the bottom of the bearing carrier, make sure the corresponding slot in the gearcase is cleaned before assembly.
You can install the propshaft first. Then slide the bearing carrier along the propshaft and guide into place. Tap in with a wooden dowel or other suitable device. Don't tap on the 'ears' of the carrier or you'll break it. Be sure where you tap is solid.
Once you've got the carrier somewhat seated in the gearcase, spread a coating of Permatex No. 3 on both the locking ring's threads, and the internal threads in the gearcase.
Install the lock tab washer and any other metal shims that came out when you took it apart, and tighten down the gearcase locking ring to 150 ft-lbs.
If you're handy with fabricating tools you can easily make your own gearcase ring tool with a hex-head to fit socket, this'll allow you to torque the cover down.
After torquing, bend up the locking tabs into the cover and you're done! Wasn't that easy!!!!
There you go, one simple way to do it, the other not-so!
HTH & Have Fun!..........ed
Align the bearing carrier and
