If you drive on a hot day about 15-20 minutes and the temp gauge is on
the "M" in the NORM range, the A/C cuts out. If the engine cools down
a little, the A/C then works intermittently.
Is there some kind of thermal sensor that can shut down the
compressor? It blows ice cold when the compressor engages.
I had just replaced the fan clutch with the correct new Motorcraft
part, still does the same cut in and out thing on hot days. The car
did not come from the factory with the auxiliary electric fan.
Thanks in advance to all for your suggestions.
Land O'Lakes Fred
When the AC quits, does the compressor quit running? If so, the clutch gap is
wide. Slip the clutch plate off, remove a shim, and reinstall it. You want less
.020", the narrower the better, without rubbing. A business card makes a good
Thanks again, Tom!
Yes, the compressor does not kick in like it is supposed to, i.e. the
compressor only then runs intermittently. Is this a function of both
heat and too wide of a clutch gap? Is there also some kind of thermal
override for the compressor?
Will do the clutch gap test tomorrow.
Land O'Lakes Fred
Yes. Once the gap gets to a certain width (due to wear), it will engage when
and then stop engaging when hot. Expansion from the heat takes the gap just past
critical point where the magnetic field can't pull the plate in.
When the compressor stops, try tapping inward on the clutch face with a
It will snap right in. This will confirm the wide gap.
There is no thermal over ride on the compressor. Protection is provided by the
and high pressure switches and is a function of refrigerant pressure.
When you remove the clutch plate, there are shims in the bore that indexes
compressor shaft.(careful, they sometimes fall out) Just remove one and check
There is often only 1 shim. If so, just remove it and check for rubbing when
disk is reinstalled. It's usually just right.
If you can't work with the shim(s) that are there, you can get a shim kit from
for about $5. This is usually unnecessary, though.
Oops, sorry 'bout that. :)
The reason for the broomstick is because it's long enough to keep hands away
moving parts and soft enough not to damage the clutch when it starts spinning. I
the handle of my long prybar, but not everyone has one of those.
Hey Fred, I just realized that I may have misled you on your original post some
back, since you are still having problems. It seemed, by your original
that your fan clutch was bad, but by your current description, that isn't the
I couldn't find your original post to check my thinking, my ISPs retention
great. I want to apologize if I steered you wrong on the fan clutch.
In my own defense, I just replaced my 12th dead mid 90's Panther fan clutch
AC season yesterday,(since April 1). I'm in Northern Ohio, so our AC season is
short, April-October at most. Mid-Late 90's Panther(Crown Victoria, Grand
Town Car) fan clutches are dropping like flies now in 2007.
No sweat, Tom. Besides, I bought a new Motorcraft clutch for under
$30, which is cheap insurance. The car is 13 years old, and this is
an almost always overlooked issue. I've seen those worn clutches
enable the fan to somewhat wobble, and that could lead to a disaster.
Land O'Lakes Fred
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