Front Radiator Fan

[Docs Ride]

We have a new 1100C and the unit has been overheating. Neither front radiator fan nor fan at engine would turn on causing overheating. Clarification - front fan will only run if AC is turned on. Turns out the temperature switch for the rear fan is bad. I can jump the switch but only rear fan will turn on.

My question - what will trigger the front radiator fan to come on if AC is not turned on? Or, does the front fan only come on with AC?

 

[10-e-c-dirt]

U said New, I say Dealer!

 

[Docs Ride]

Ha ha, yes that is a fair statement. Unfortunately, it was at the dealer last week and they misdiagnosed it. One thing that confuse them was they had the air conditioning running. When the air conditioning is running the front fan stays on continuously. With that fan running for the air conditioning, it masked the problem.

Over the weekend I discovered that it would overheat when the air-conditioning was not running… Because the fan was not running. I spoke with a very helpful technical service guy at Messicks equipment today. It sounds like once I get the temperature switch fixed the front fan should start working along with the rear fan.

 

[Doc]

I think the front one is just for A/C. Fix the rear one and see if you are still overheating.
What year 1100c do you own?

 

[Docs Ride]

I think the front one is just for A/C. Fix the rear one and see if you are still overheating.
What year 1100c do you own?

That would make sense. It is a 2023 with about 25 hours on it….nearly all of those hours have been with AC/front fan running.

 

[Doc]

Oh, not even broke in yet. Warranty? If so I think I'd talk to the dealer if you have a good one you trust.

 

[Docs Ride]

Yes, it is under warranty and will be going back to the dealer. It was at the dealer all last week and they could not determine the problem so I am trying to do some leg work on solving the problem so that it won’t sit there too long. Thanks for your input!

 

[Doc]

Yes, it is under warranty and will be going back to the dealer. It was at the dealer all last week and they could not determine the problem so I am trying to do some leg work on solving the problem so that it won’t sit there too long. Thanks for your input!

Oh, that is truly disappointing. We expect more from the dealers. Overheating should be straightforward to diagnose. Perhaps another Kubota dealer not to far from you that you might try? I'd hate being without my new machine but I'd drive a bit further for a more competent dealer (if that is the issue).

 

[Docs Ride]

Update: here is what I have learned on the X1100C that has two radiators….. There is a single temperature switch at the thermostat housing that controls both the mid vehicle fan and the front fan. Here is how it works…. When the engine coolant temperature hits a certain threshold the temperature switch activates the “fan circuit”. The mid vehicle fan will turn on first. If the ECU/Brain sees that coolant temperature does not drop enough or that the temperature continues to rise the ECU/Brain will also energize the front fan so that both are running. If the single temperature switch is faulty then neither fan will run. The one exception to all of the above is if you turn on the AC the front will come on regardless of engine temperature.

 

[Doc]

Update: here is what I have learned on the X1100C that has two radiators….. There is a single temperature switch at the thermostat housing that controls both the mid vehicle fan and the front fan. Here is how it works…. When the engine coolant temperature hits a certain threshold the temperature switch activates the “fan circuit”. The mid vehicle fan will turn on first. If the ECU/Brain sees that coolant temperature does not drop enough or that the temperature continues to rise the ECU/Brain will also energize the front fan so that both are running. If the single temperature switch is faulty then neither fan will run. The one exception to all of the above is if you turn on the AC the front will come on regardless of engine temperature.

Fantastic investigative work. Good to know information. Thanks so much docs ride.