Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Welcome to JUST ANSWER small engines, let me try to help you !! I don't know it all, but maybe together we can get you a satisfactory answer!
The Yanmar engine. You say you have fuel? Fuel squirting at the high pressure lines if you loosen them and crank? Smoke from exhaust when cranking? How did it quit? Could fuel be contaminated with gasoline?
Unit has kill solenoid for engine kill only. I assume it is not stuck in the off position?