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Topic: ‘03 ISM 450 thermostat  (Read 459 times) previous topic - next topic

‘03 ISM 450 thermostat

Good morning everyone.

I went to Cummins parts to look for this info .
It looks like the thermostat starts to open at 180 degrees F and is completely open at 201 degrees F.

With this in mind, should the cooling fans be running on high before 201 degrees?

Are there any other systems that turn the cooling fans on even if engine temperature is below 180 degrees?

Could the fuel, hydraulic and coolant radiators be dirty and cause the fans to start?

I did not hear my cooling fans for the first 2 years of ownership. Then one day I started the coach and the fans went to high. I've cleaned the plug at the electronic controller. Sometimes when I turn on the high idle after initial 10 minutes the fans go to high. I also think I hear the fans on high when traveling down the road but my engine temp is not over 182.

What temperature wax bung should be installed in this situation. I've read the thermostat should be wide open when the fans kick on so I'm thinking about 210.


Thanks everyone.

Re: ‘03 ISM 450 thermostat

Reply #1 –
The only thing that makes the fan go to high speed is the controller and when it fails it goes to high
speed.

Re: ‘03 ISM 450 thermostat

Reply #2 –
Thanks Peter,
They are not on high all the time

Re: ‘03 ISM 450 thermostat

Reply #3 –
I would think the temperature setting in the controller is off. I have a 210 wax controller on mine
and I did partly the same as Scott so I can turn mine on manually.