Have a somewhat similar problem with ours (same brand, but SP55s model) except that the oil was draining out of the reservoir into the bilge
at the motor
end. First fix attempt was to replace the shaft seal
on the gear
leg shaft, which is the only thing that can be done with the boat in the water
. A bit of a pain, but not too bad if you have access, involving taking the motor
off and the using a pick of some sort to get the old seal out and an appropriate size socket to seat a new one.
In my case, a new shaft seal
worked for awhile but the leak returned. Also, had a bit of seawater leaking into the bilge
past the gearleg to hull gasket
After hauling for the season, I removed the gearleg from the boat (motor had to come off again, then the prop, then the motor mount and gearleg). The motor removal
is the pita part, but gearleg removal
was very easy. If you have new "O" rings, shaft seal, mounting gasket
and caulk on hand, and remove the motor beforehand, you probably could get the job done in a couple of hours haulout. I am told that the critical part in remounting the gearleg is to ensure that it is centered in the tunnel when/as the two motor mount to gearleg bolts are tightened and that no caulk gets into the threaded bolt holes. Use tongue depressors wedged between the ends of the prop blades and the tunnel for centering.
of our gearleg showed several things: that there was water in the oil, that the shaft where the shaft seal is was corroded a bit probably causing the seal failure, that the two shaft "O" rings in the motor mount were worn allowing water to seep by and that all of this was all almost certainly caused by an installer who did not caulk both
sides of the gearleg to hull
gasket. He used no caulk between the gasket and the hull.
IMTRA has the gearleg and I am waiting on the verdict as to whether it is beyond repair or not. (i.e. If they can smooth out the corroded shaft to tolerances or not and whether there is any internal damage or not). A new gearleg is almost a "boat buck" and used ones are almost unobtaniuim. Gearlegs evidently cannot be taken apart and worn internal parts
Mark Raeder at IMTRA has been very helpful throughout. IMTRA has given me excellent advice and customer service
(including on a previous stern thruster problem I had) even though the thrusters were not purchased through them.