I'm thinking of replacing my engine coupler myself

[pascavone]

My boat was taking in about 4" of water a week, and figured it was the drive bellows or the shift cable.
But actually it is the tiller rod gasket which is in the gimbal housing. You need to take off the outer gimbal ring to get to it.


The way you can tell a long term leak is to look for the white salt track running in the boat. The ocean water drys and leaves a salt trail.

Since the motor is out, it a good time to pre the boat for it's 2nd life with all new gaskets.

Finally, my boat had after market COSC mainfolds and everyone is telling me they are crap. $350 vs. $550 each for mercruisers. They have a cermic coating of a TE coating, your still looking at 5 years max.

They way to check your mainfolds is by using a heat dector gun that shows infered hot spots when the engine running, look for salt tracks or drippping, or take the elbows off and look for water.

any leak into the mainfold will drain into the cyclenders via the exhaust valves. the good thing is the raw water pump only feeds those mainfolds when the boat is running, and the engine will steam off any water with the 600 degrees of exhaust gas. the fear is you let the water sit in the cyclenders and the engine get stuck.

[pascavone]

This is the "mother" of all leak, when this gimbel shaft seal leaks, and the salt water corrode shaft, bushing, and nut.
This is very common for a 10 year old boat, since the seal is a simple rubble ring with a contraction spring on it to contract around the gimbel pin...(think of it like a condom)
You have to take the engine out to remove the gimbel assemble from inside the boat.


This is my old gimbel housing, then engine rear mounts rest on this and had corroded away.

This the new one, note the bottom bolts are under your Y-pipe.