Just picked up a P5xlt... Im having a really hard time starting it. When I rotate the flywheel, it locks up when the piston is at the top. Ive tried starting it on an AE box and burnt out the motor in the box. Tried again on my Ofna box and finally got it started and ran it for a tank and a half but chewed up the wheel on the box quite a bit. Is this normal for the engine? Its my first time with a new engine so... this is kinda new to me. Thanks!