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AC clutch issues or what?

tobijohn on Sat December 05, 2009 8:19 PM User is offlineView users profile

Year: 2000
Make: Ford
Model: Ranger
Engine Size: 2.5
Refrigerant Type: 134a
Ambient Temp: 80
Country of Origin: United States

Several months back I noticed that the AC would cut out intermittently. After monitoring things for a while, it seems that this was occurring in 3rd or 4th gear at low rpms. After a stop, one I began proceeding again the AC returned to normal. The pressures are within spec and on the Maxcool setting it's cold enough to give you a headache. I'm wondering if this is a control issue rather than a mechanical one because the behavior is very consistent. Any ideas? TIA...

Chick on Sun December 06, 2009 8:27 AM User is offlineView users profile

check your clutch gap (and charging system for correct voltage at idle) when it stops, tap the front hub inwards carefully of turning belts, if it grabs, you may have to adjust the clutch gap.. Also try tapping or jumping the cycling switch, if that starts it, you might need a new switch, thats where I would start anyway.. hope this helps..

Email: Chick


Freedoms just another word for nothing left to lose

tobijohn on Sun December 06, 2009 9:50 AM User is offlineView users profile

Thanks, I'll give it a try this week...

tobijohn on Sun December 13, 2009 9:13 AM User is offlineView users profile

OK, once it had disengaged as mentioned previously I tried tapping lightly on the front of the AC clutch with a screwdriver and mallet . It engaged for a couple of seconds and then disengaged again. Did this a couple more times, same results. Does that indicate anything?

Cussboy on Sun December 13, 2009 11:23 AM User is offline

That sounds like an AC clutch gap issue.

mk378 on Sun December 13, 2009 2:45 PM User is offline

The gap is too wide. Take the shaft nut off and remove the clutch plate, then remove some of the shim washers from the shaft. Reassemble and make sure the clutch does not rattle or drag when de-energized. The gap should be about .020 inches.

tobijohn on Sun December 13, 2009 2:51 PM User is offlineView users profile

Thanks for the responses. What would cause the gap to widen like that, just normal wear? 105K on the odometer...

NickD on Wed December 30, 2009 2:30 PM User is offline

CCOT systems tend to cycle a lot, really a lot. Especially in cool weather when you have to turn the defrosters on. There, your compressor is expected to accelerate from zero to engine running speed in an instant. On some cars, I have disabled that defrost feature, doesn't to very much anyway as cold air really doesn't contain that much moisture. On others, wipe off the windshield with a rag or just roll down the window that clears it up. But can't do that with the wife in the car.

It's not only hard on the clutch, but the compressor as well, in particular the seal that has rock hard rubber when it's cold outside. I see no improvement in just running the defrost with the compressor off, that hot air blast dries off the windshield quickly. Also helps not to breathe as that puts plenty of moisture in the interior air. Dogs really can fog up the windows in a hurry. But for some strange reason, all the vehicles come that way.

I prefer pulling the compressor plug and applying a variable voltage to the clutch coil so I can see the pull in and drop out voltage. I don't go whacking the hub with a baseball bat when a simple feeler gauge tells me the story in a hurry. Prefer setting the gap at 20 mils for most cars, but could to know the specs, on some earlier Fords with that rubberized hub, have to set it at 9 mils. GM's require a special tool for that.

That constant cycling also stresses out the entire belt train wrecking the tensioner, idler, and other limited lubricated bearings in the belt drive system. Talk about a self destructing mechanism, that's what we buy today.

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