I really hope someone can provide some help. Replaced bad fan clutch on 2007 Ford Explorer back in June. Didn't fix problem so replaced again. Sti not fixed. Replaced with used parts both times. Situation is after driving 30 minutes plus fan sticks in on position like wide open and sounds like jet engine when gas is pushed. My mechanic does not know. Says may be my computer but there are no other signs. No fluids leaking or low or anything else wrong. Any thoughts?

 

This vehicle is with rear wheel drive correct ?
Lets look at a lot of possibilities,

Both clutches defective ,
Radiator blocked so air cannot get through to allow fan clutch to disengage,
Outside temp where you reside really high requiring constant cooling of coolant,
Air conditioner running constantly causing hotter than normal air passing on to radiator,
Air conditioning condenser blocked externally so sufficient air not available to cool fan clutch
There may be a few more possibiles, but this should provide some things to check.
If engine is running hot and radiator is removing the heat and blowing it at the fan clutch sensing mechanism
Is there some particular reason for using used /questionable parts?
Hope the parts are coming from identical type vehicle .

 

Vehicle is 4 wheel drive and does not run hot. Temp hand never above normal range. Supposedly mechanic checked radiator and all was fine. There is no pattern to this. For example it's 93 degrees today and I drive vehicle about 30 minutes high humidity. Did not make noise. Cannot find a pattern.

 

To answer your question on using used parts - they are much cheaper and was hoping they would work. What are the possibilities I have put 2 used parts on and neither work ? Again, I can not determine a pattern with the noise/symptoms - doesn't matter if AC is on or not, no pattern.


I'm at a loss.

 

If it is something you can definitely see will or won't work sure take a chance with used stuff, but when you compare the extra trips and work you may have come out ahead with new fan clutch.
Circumstances do dictate to a certain extent what we do and "Sometimes Benji gets the bear and sometimes the bear gets Benji". Can't win them all !

 

I know, sometimes trying to save money doesn't work. I'm definitely second guessing my decision to go with used parts now, after the fact. Was also reading on a thread someone had a bad Thermo Bypass which was sending a message the transmission temp was too high so the fan would engage. Again, my temp has never gotten out of normal range. I don't know what to do. It has been really hot here - 90+ and very humid but this vehicle has never acted like this before, and I bought it brand new. Not sure what to do.


Also, no diagnostic codes show up when vehicle is hooked to computer. Any more ideas ?

 

So we are on the same page,
if your vehicle was with front wheel drive and had an electric fan motor(s) then relays, temp controls and computer outputs could influence their operation.
I believe rear wheel drive vehicles have a viscous fan drive that is influenced by the temp of the air coming off the radiator and if the air is hot the fan almost locks up to provide maximum air movement. There can be problems where the fan stays locked and moves a lot of air , but also makes a lot of extra noise. It can also go the other way where it lopes along and doesn't move sufficient air resulting in hi temp problems.
If all the items previously listed check out OK, it is possible the fan clutch is staying in the max air movement position . Common problem is they could leak and not move as fast as required. When you first start the cold engine the fan should turn fast then slow down in about 5-10 seconds. If it stays fast it is defective.

 

Hanky - thank you so much for your helpful answers. My vehicle is 4 wheel drive. I am not experiencing any overheating problems, quite the opposite it seems. It seems the fan is running almost too fast and is making the extra noise and revving some when gas is pushed. Another note, when the vehicle is cold after sitting for a couple of days the fan does come on fast but then shuts off after a few seconds. So, it seems to be working like it should in that case. This is really confusing. Again, I'm lost.

 

Question - could I have a bad thermostat that would be causing the clutch fan to come on and be very loud at times ?

 

Just thought of something else to add - when clutch fan was replaced back in June for the first time symptoms were really really bad, not doubt needed replacing. An update to the PCM was also done and my mechanic said the update was to the cooling system. Any chance this update can be making the fan perform differently ? Run louder etc? Just a thought. Anxious to hear what other Ford owners have to say about this. Again, vehicle not overheating and no other symptoms other than loud fan noise at times with no distinguished pattern.


Thanks