RE: Hydro-Lock!!!
 

There is a chance DownUnder is correct. Remember the oil is in the fuel.

RE: Hydro-Lock!!!
 

Well if the engine turns over and won't after you install the prop and tighten it down, your missing something.

RE: Hydro-Lock!!!
 

It may be a good idea to remove the engine form the plane and at least partially disassemble the engine, If you don't feel comfortable with this ask someone in your local area to maybe give you a hand. There is also a video on youtube of how to disassemble a model 2 stroke. This may be something you'd be interested in viewing .

This is of course assuming that the prop/spinner is not hitting anything and that it is the crank shaft that isnt moving.

Steven.