Dave & Jonathan,
You both seem to have a similar problem and it appears to be the key that sets the timing on the engine and this could be sheared. The key should be about 1/2" long by 1/8" thick and all sides should be flat, so if it has a ridge in it the timing will be out.
Check this first and let me know how you get on.

Regards,
Bruce


Regards,
[Linked Image]

Bruce


Please do not PM me asking for support. Post on the forums as it helps all members not just the individual.