You can test if the relays and the triac of the engine work well and replace if you find any broken, greetings.
If you have an engine of another similar machine, place it and test if it works, you can also test the direct motor to see if it works or not, greetings.
Hello. Solved problem. They were the spent coals. Try another engine that also had the defective coals; that's why I'm disconcerted. A thousand thanks.