94 CROWN VIC A/C CUTS OUT ON HOT DAYS...

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

Reply to
septicman
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When the AC quits, does the compressor quit running? If so, the clutch gap is too wide. Slip the clutch plate off, remove a shim, and reinstall it. You want less than .020", the narrower the better, without rubbing. A business card makes a good go/no go gauge.

Reply to
Tom Adkins

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

Reply to
septicman

Yes. Once the gap gets to a certain width (due to wear), it will engage when cool, and then stop engaging when hot. Expansion from the heat takes the gap just past the 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 broomstick. 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 low 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 with the compressor shaft.(careful, they sometimes fall out) Just remove one and check the gap. There is often only 1 shim. If so, just remove it and check for rubbing when the 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 Ford for about $5. This is usually unnecessary, though.

Reply to
Tom Adkins

If this brings "hurricane" back, it's your fault Tom!

Reply to
Neil Nelson

Oops, sorry 'bout that. :)

The reason for the broomstick is because it's long enough to keep hands away from moving parts and soft enough not to damage the clutch when it starts spinning. I use the handle of my long prybar, but not everyone has one of those.

Reply to
Tom Adkins

Again, Tom, thanks !!

Land O'Lakes Fred

Reply to
septicman

Hey Fred, I just realized that I may have misled you on your original post some time back, since you are still having problems. It seemed, by your original description, that your fan clutch was bad, but by your current description, that isn't the case. (clutch gap). I couldn't find your original post to check my thinking, my ISPs retention isn't 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 for this AC season yesterday,(since April 1). I'm in Northern Ohio, so our AC season is fairly short, April-October at most. Mid-Late 90's Panther(Crown Victoria, Grand Marquis, Town Car) fan clutches are dropping like flies now in 2007.

Reply to
Tom Adkins

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.

Thanks again.

Land O'Lakes Fred

Reply to
septicman

Does removing these clutches require any special tools?

Reply to
Ashton Crusher

yes, there is a fork-type tool that goes over the four bolts on the pulley.

Reply to
septicman

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