Questions and Answers
Explorer A/C Runs Hot And Cold
Q. Dear Sir, I have a 1992 Ford Explorer, automatic, approximately 120,000. The problem I'm having is with my air conditioning. I live in Arizona and have two small children and cannot afford to be without it. The problem is whenever the air conditioning is on and I stop in traffic or at a red light, it starts blowing hot.
We have spent over $1,500.00 in the past two years to have major, various things fixed because we cannot afford a new (or used for that matter) car at this time and are trying to make this vehicle last as long as possible.
I was told from a mechanic that in order for the air conditioning to stay blowing cold, there must be a constant flow of air through the front end. Well, unless I never stop, that wouldn't be a problem. Is there a solution to fix this problem? We are melting when it gets over 100° (which is now).
Thank you
JulieA. If everything is working right, there should be little change in the cooling ability of the A/C when stopped or moving. Seeing as how it does work when in motion does indicate it is an air flow problem. I would have to think the fan clutch is not doing it's job by engaging when it starts to heat up.
Here is how you can check it:
Fan Clutch Operation
- Run engine at a fast idle speed 1500 RPM until normal operating temperature is reached. This can be done more quickly by blocking off the front of the radiator with cardboard.
NOTE: Regardless of temperatures, the unit must be operated for at least five minutes immediately before being tested.
- Stop engine and, using a glove or a cloth to protect the hand, immediately check the effort required to turn the fan.
- If considerable effort is required, it can be assumed that the coupling is operating satisfactorily.
- If very little effort is required to turn the fan, the coupling is not operating properly and should be replaced.
- The clutch fan may be tested while the vehicle is being driven. To check, disconnect the bi-metallic spring, and rotate it 90°counterclockwise. This disables the temperature-controlled, free-wheeling feature and the clutch performs like a conventional fan. If this cures the overheating condition, replace the clutch fan.
Bi-Metallic Coiled Spring RemovalFan Clutch Fluid Leak
Small fluid leaks do not generally affect the operation of the unit. These leaks generally occur around the area of the bearing assembly, but if the leaks appear to be excessive, engine overheating may occur.
- Check for clutch and fan free-wheeling by attempting to rotate fan and clutch assembly by hand five times.
- If no drag is felt, replace the clutch.
Fan Clutch Noise
Fan clutch noise can sometimes be noticed when the clutch is engaged for maximum cooling. Clutch noise is also noticeable within the first few minutes after starting the engine while the clutch is redistributing the silicone fluid to its normal, disengaged operating condition after settling for long periods of time (over night). However, continuous fan noise or an excessive roar indicates the clutch assembly is locked-up due to internal failure. This condition can be checked by attempting to manually rotate the fan. If the fan cannot be rotated manually or there is a rough, abrasive feel as it is rotated, the clutch should be replaced.
Fan Looseness
Lateral movement can be observed at the fan blade tip under various temperature conditions because of the type of bearing used. This movement should not exceed ¼" (6.5 mm) as measured at the fan tip. If this lateral movement does not exceed specifications, there is no cause for replacement.
Also make sure the radiator fan shroud is in place and not broken. This is very important to make sure air is drawn through the condenser and radiator.
Now you know all there is to know about fan clutches. If it passes all these checks, the cheapest wa out is to have an electric cooling fan installed and connected to the A/C in such a way that when the A/C is turned on, the electric fan will go on.
Additional Information provided courtesy of ALLDATA
