A week or so ago, I posted a problem I was having with my generator blower not working properly. It would shut down and then not restart for several hours. After checking all fuses, connections and power to the electric motor it appeared that the thermal protection on the motor was shutting it down. I'm traveling across country so I replaced the 14 year old motor but the electrical supply house only had a motor with a manual reset. I installed the new motor and within 30 - 40 minutes of operation, it shut down again. (thermal protection switch). The water temperature in the radiator when the blower is running is about 165 - 170 degrees depending on the load. This seems to indicate that the radiator is functioning properly. To be safe, I replaced the engine thermostat and replaced both radiator caps. I've managed to keep the generator from overheating when the fan stops by keeping a watch on the gauges and shutting down the generator when the blower light goes out.*

The exhaust baffle is new. It is in place and clear of any debris. The inlet for air flow to the radiator is open and clear of any debris. The coolant is clean and at the proper levels. Yesterday, the generator and blower worked properly for three hours while the bus was moving. Then suddenly the blower stopped. I know nothing about the two relays in the watchdog but would they have any impact on the fan motor overheating and shutting down? The squirrel fan that draws air through the radiator does not appear to have any issues. It spins freely and the shaft has no play. The motor drives the fan in the proper direction and it exhausts heat through the baffle.

The motor does not appear to be in a bind. It sits properly on the mounts and is lined up with the fans pulley. The fan belt is not too tight as to cause an overload. I'm stumped and looking for any advice!
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Thanks,
Richard Barnes