Our timecutter swx5050 has 430 hours and stopped running last week while cutting the grass. The oil was changed at the beginning of the season and is clean and at the full level. Recently the mower began to surge instead of maintain full throttle speed. I think this may be due to a carb blockage - perhaps courtesy of ethanol gas. Anyway I didn’t have time at the moment to remove and clean the carb. My son began cutting the grass and experienced difficulty cutting due to the inconsistent engine speed. The mower stopped several times. Then it stopped altogether. Now it will no longer turn over. It just clicks.
When I shorted the starter solenoid, it seems that the starter is energized but no movement. I don’t think the solenoid or starter are at fault because I removed the plugs and tried turning the motor with a breaker bar on the pulley bolt. No movement in either direction. I ruled out the electric pto being stuck on since I can turn the pulley under the pto. I also jacked the machine up, released the parking brake, and was able to rotate both rear wheels but not turn over the engine with the breaker bar. I concluded that the drivetrain is not preventing the engine from turning.
I am not sure what to try next before tearing the engine dow. Any suggestions/fixes or theories what might be the problem?
Thanks!