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Radiator fan

Yahoo Message Number: 57200
OK, all this discussion about the fan controller has me wondering. Today, I am changing my oil. First time I have done it myself. So I started it up, to get it warmed before draining the oil. I let it run, and run. The temperature will not get to 130 degrees. I looked under there, and the fan is running. I don't know what speed it is running, but it is running. Is that normal?

Al Colby

2000 Intrigue 10979

Re: Radiator fan

Reply #1 –
Yahoo Message Number: 57201
It would be normal for the fan to run at low speed while the motor is cool. Then run at high speed when the coolant temp reaches about 204-205 bring temperature down to about 195. If the fan is running at high speed with motor cold, that would be abnormal. Thus the test procedure for fan controllers requires measuring fan speed and testing sensors. Running the motor to the 130 temp you report should have stirred up the oil (so to speak) to drain completely. You need to drive the coach to get to normal operation temperature. For the purpose of heating the engine oil before draining,
When I started the fan controller poll, I wanted to see if there was any model year with more problems. With the votes that have been cast, looks like a common problem with this system.

Dave

07 Inspire 52060

Re: Radiator fan

Reply #2 –
Yahoo Message Number: 57207
Hi Al,

In my travels I have heard two schools of thought on warming the engine to change the oil. One side feels that the oil flows better when it is warm/hot making it easier and faster to empty the oil pan The other side says that when you start the engine it pumps the oil back up into the engine block and head and that it now take a while to slowly drift back down to the pan so you leave a certain amount in the engine. Certainly 15W40 is not all that thick at an ambient temp that one would want to be out their changing the oil.
I honestly don't know the correct answer but I have the feeling we are about to find out from the engine guys. I have always warmed them up but have often got it too hot (not my Cummins as it is like yours) and had to wait in the end anyway.

Don Seager

2004 Allure 31046

Re: Radiator fan

Reply #3 –
Yahoo Message Number: 57215
Al,

On mine the fan is always running at least at low speed. I don't believe that there is an off condition. But I, and I think you, have variable speed logic in the FDCA that provides for a programmed speed ramp up from low speed, through multiple steps, until conditions demand full speed.

George in Birmingham
'04 Allure 31038

So, I think you are ok.
George in Birmingham
2003 Magna 6298

Re: Radiator fan

Reply #4 –
Yahoo Message Number: 57221
George,

For all that I can see the FDCA is not that sophisticated. I believe that there is actually only a high and low speed condition as determined by multiple inputs. The speed of the fan is actually controlled by the flow of the hydraulic fluid as it relates to the rpm of the engine. On low speed the FDCA restricts the flow to force a slower range of speeds as the engine rpm goes from idle to red line and when needed the restriction is removed by the FDCA allowing a faster flow of fluid thus rotating the fan at a faster speed for any given engine rpm.
On mine, you are correct, there is no off and the fan is always running at some speed.

Don Seager

2004 Allure 31046

Re: Radiator fan

Reply #5 –
Yahoo Message Number: 57235
Don,

I agree that the FDCA is not a particularly sophisticated device. But, whether it variable speed or two speed depends on the part number and control methodology and programming.
If you read the document in this link you will see that part of the programming is for ramp up time delay. This parameter defines the time it takes to ramp up from low speed to high speed. There is also a ramp down parameter to control the reverse. I can even hear the speed increase on my fan as I climb a grade.
Temperature will rise from 190 and when it hits about 199 (Silverleaf) the fan will start to increase in speed. Within about 45 seconds it will ramp up to full speed. Thus, when it is cold out the max temp I'll see is about 201. In the heat of the summer I'll see as much as 205 before the fan speed is high enough to begin to cut the coolant temperature.
Don, yours may be high/low. Mine is variable as are many others. The problem in discussing this is that everyone has what they have. Our friend George Harper has an FDCA on his identical to mine '04 Allure that has only 4 wires to his FDCA. Mine has 8. I don't know what yours has. I know why these applications are different but it just doesn't matter. You have what you have.

George in Birmingham
'04 Allure 31038.

http://www.sauer-danfoss.com/stellent/groups/publications/documents/product_literature/11005336.pdf
George in Birmingham
2003 Magna 6298

Re: Radiator fan

Reply #6 –
Yahoo Message Number: 57252
George

Based on previous posts on this thread, I'm thinking that the reason I have 4 wires on my fan controller and you have 8 is that my controller is receiving inputs from the engine ecm. So, that brings up the issue of the temperature sensors. I wonder if you have two sets of temperature sensors - one for the engine and one for the fan controller, whereas I amy have only engine temp sensors. If that is true, then maybe my controller gets its temp readings via the engine ecm?

George Harper
04 Allure
31093
 

Re: Radiator fan

Reply #7 –
Yahoo Message Number: 57263
George,

I don't think you get temperature data sent from engine ECU to the FDCA. I think that the ECU takes the data that it has and sends a variable voltage signal to the FDCA that represents the ECU's calculation of fan speed required. Keep in mind that there are three inputs to my FDCA. Water temperature, Charge air temperature and A/C pressure as sensed by the dryer trinary switch. Yours also has the trinary switch so that data is considered by the ECU in addition to the temps.
I believe that I have two sets of temperature sensors as you suggest. My chassis wiring diagram in my source for that belief.

George in Birmingham
'04 Allure 31038
George in Birmingham
2003 Magna 6298