How To Replace Prop Shaft Seal

In this video, Mike Gridley describes how to replace prop shaft seals on outboard carburetors. He starts by removing the Allen screw that locks everything together. Then, he uses a Mercury specialty tool to remove the locking ring.

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He then uses a flathead screwdriver to fold back the locking tab and back the cover nut out of the gear case. He says that this would normally require a half-inch ratchet, but he does it by hand. He then uses a gear puller to remove the bearing carrier from the gear case.

Mike then disassembles the gear so he can get the shaft seals out. Next, he cleans out the bore and puts Loctite in it. Then, he puts the outer seal in place with its lips facing out and presses it into place with a Mercury seal installation tool. He does the same thing to the inner seal.

Mike then mixes some Mercury 24c and synthetic gear lube and applies it to the bearing. He places the thrust washer on the bearing and drops it into place. Next, he places the o-ring, washer, and gear into the carrier. He then applies Mercury’s perfect seal and reassembles the outboard carburetor.