hello, my older brothers have a 1st generation nitro 4 tec with an old .15 . i believe its siezed because last time i was at there house the engine wouldnt turn over and i couldnt turn the flywheel. but anyways its been sitting for many years and i might be trying to repair it soon. if the engine is siezed what should i do. is there a way to unsieze it like putting oil or wd40 in the glowplug hole and let it sit. or should i buy a new piston sleeve and clean the original piston? we dont have much money to buy a new engine.