if it is jammed put a few drops of after run oil in the glow plug hole & let it sit for a bit. take the engine out of the buggy & if you have a heat gun or hairdryer heat it up. with it out of the buggy you should be able to get a grip on the fly wheel to turn it out. for the first few tanks i had to use a screwdriver to pop the fly wheel out of lock until it freed up enough to pop with my finger. it's had well over a gallon through it now (nearly 2) & it still gets stuck every now & then. they hold their compressin really well. i'll definitely be getting another one of these engines.