Ian,

Your problem was caused by a small amount of  saltwater water passing the foam and lip seals.

When was the last time it was serviced? It should be serviced every two years.
Do you use the locking pin? If not, even new seals may leak a little in rough seas.

What commonly happens is that the above mentioned small amount of saltwater causes oxidation (rust) on the cast iron base of the electric motor. This causes the clearance for the tube to become smaller and the tube becomes bound inside the cast iron base of the motor.

I would not recommend heat because you may damage the tube. I would not recommend pulling the bow thruster out as you described because I think that you will break the foot.

The best solution is to spray copious amounts of penetrating fluid through the bolt holes and into the space between the tube and base of the motor from the bottom. Using the clamp-on special tool apply as much downward force on the tube as you can, then find something to vibrate that cast iron base... possibly an impact tool. Don't hit it with a hammer, because it is cast iron and it will break. You will also need lots a patience because it may take hours of vibration and downward force. Possibly a rubber mallet could work as well to provide enough shock while the tool is applying downward force.

There is another method which works, but usually only with a light amount of rust. That is to disconnect the cable at the top of the motor and from under the boat push the thruster up and pull it down quickly. The shock of hitting the bottom may break the tube loose from the motor. If this doesn't work in 6-8 tries, it probably won't work at all.

Of course everything I suggested could be overdone causing something else to break.

You did not say where you are. If you were near me, or possibly another owner, you could possibly have a volunteer to help you.

Bill Rouse
BeBe Amel 53 #387
Currently Trinidad, Crews Inn Marina
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