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stevekaufman's avatar
stevekaufman
Explorer
Aug 21, 2013

Engine overheating on Cummins ISC 350 Fan not turning

I have a 2003 Allegro Bus with a Cummins ISC350 engine that is overheating. The fan is not turning. It is a side mount radiator. Was wondering if it is the hydraulic pump or the solenoid and how I w...
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wolfe10's avatar
wolfe10
Explorer
Aug 21, 2013
Call Freightliner in Gaffney in the morning with your VIN and ask them if disconnecting should default the fan to high. If true and that did not turn the fan, next thing would be to verify that the fan motor is not frozen up-- can you turn it by hand?

Also, verify with Freightliner that the pump that supplies the fan motor also runs the power steering. Some applications use a separate pump and reservoir for the fan motor.

Do you have a filter in the system-- might change it.

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