my revo with the 2.5R engine has been in storage for almost 2 years. well, i pulled it out to get it ready to run, and alas, the motor is siezed. i remember setting the piston at BDC after i prepped it for storage. i know my curious son (13) messed with it not long after i stored it. anyhoos, i charged up my ez start battery, and nothing when i plugged it into the truck. i took out the glow plug and found the piston is at or near TDC. so far i've filled up the cylinder with WD40 but i haven't been able to turn over the motor by hand yet. any suggestions on how to free the stuck piston?