Beeza,

I would remove the engine from the drive unit and check which is stuck. Did you ever lube the lower unit? Did you put it away with water in it?

The basic engine is a K&B 3.5 ABC schnuerle glow, if it's like mine. You might try some fuel to loosen it up. Also check that the carb is working freely.

Make sure you tell the person receiving it what you have done to free it. The person may want to take further steps like checking the bearings closely and checking that the wrist pin is not stuck to the conrod.

George