Dolphin motor repair
Dolphin's motors are very expensive, so is a rebuilt as far as you can find them.
However most of the time the motors can be repaired. The spi seals leak after a while and some water get into the bearings that rust.
It can be that bad that the propeller cannot be moved.
Most of the time the rest of the motor is in good shape. You just have to change the spi seals and the bearing and it works