Hello, My customer complains of no power when lifting and/or driving. When unit is in neutral, engine will rev up to 2500 - 3000 RPM - exhaust sounds very noisy but has no leaks around muffler?????No Smoke engine purrrs like a kitten, I have changed ignition system, and rebuilt CA55 Carburetor. I was thinking of timing chain or compression test, Governor assembly. Any ideas so i can sleep at night. Customer is about a 3 hour drive. need as much information as possible.