Hi guys,I,m new to this game..just bought a new EB4 Thunder tiger pro 21. I've started to run in(1 tank) engine stuck..wouldnt turn over. Took back to shop,owner turned flywheel with screwdriver to free up. Started to run -in again,but motor keeps sticking? Have to keep turning motor over with screw driver to start. On 3rd tank now. Is this normal? Thanks