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My AC will blow cold for a while then blow hot for a few mins then cold then hot, etc. It has charge according to the diy gauge I have. Any Ideas?
 

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Clutch on the compressor cycling with the heat/cold thing?

A real set of gauges is best for troubleshooting the AC system -- too much or too little charge or plugged orifice tube, bad pressure switch, mouse nest in the evaporator, etc
 

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Check your clutch on the compressor. It's probably not staying engaged.

A) it is out too far - gap between the compressor and the engaged clutch making it hard to stay engaged. B) the clutch is wearing out and not staying engaged. Mine was the latter. Once replaced, it always stays engaged.
 

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Check your clutch on the compressor. It's probably not staying engaged.

A) it is out too far - gap between the compressor and the engaged clutch making it hard to stay engaged. B) the clutch is wearing out and not staying engaged. Mine was the latter. Once replaced, it always stays engaged.
The clutch is intended to cycle on and off to keep the evaporator from icing up(there is a switch on the evaporator) -- this leads to a lot of wear on the clutch face surfaces -- when the clutch is hot, the magnetic field is not as strong, so it may cycle off and not be able to cycle back on because of excessive clearance.

Low voltage will also cause this action above

There is a shim behind the driven part of the clutch that can be removed, to get a "little more" out of the clutch -- looking for about .010 - .020 clearance(gap) on the clutch face
 

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A clogged orifice tube will also do the same. I had similar and my AC was freezing over. I had a new orifice tube installed system flush and I reduced the gap on the compressor clutch. I then used the AC sparingly (only when absolutely necessary) and got 2 more seasons before I had to have the whole ac system replaced (done last week). Likely any fix is a band aid. Budget $1200 for a replacement down the road.

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Discussion Starter #6
Looks like a new clutch hub fixed it for now, thanks y'all.
 

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FYI, the Ford ranger had a nice little piece of equipment installed on the A/C system that can be done to your truck to make the A/C even colder. I did it to mine and my A/C will freeze my b.... Off.
It's a cable operated bypass that goes inline with your heater hose's, when you have the A/C on it will stop flow to your heater core which in turn reduces the heat the air has to pass before it passes through the A/C. The end result is about a 10 degree colder A/C. I did it to my 2001 7.3 and it works.
 

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Can you explain how to do it? My brand new AC will barely cool my extended cab unless I put it on max. It's 95 here in Savannah

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Tie the vacuum valve in the heater hose, so that it stays pulled forward -- zip tie or small wire -- sounds like your blend door seal in the heater is not closing well enough -- closing that valve will stop the hot water in the heater
 

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The clutch is intended to cycle on and off to keep the evaporator from icing up(there is a switch on the evaporator) -- this leads to a lot of wear on the clutch face surfaces -- when the clutch is hot, the magnetic field is not as strong, so it may cycle off and not be able to cycle back on because of excessive clearance.

Low voltage will also cause this action above

There is a shim behind the driven part of the clutch that can be removed, to get a "little more" out of the clutch -- looking for about .010 - .020 clearance(gap) on the clutch face

Did you have a low voltage issue at all? If so, what was your fix?
 

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Can you explain how to do it? My brand new AC will barely cool my extended cab unless I put it on max. It's 95 here in Savannah
TAKE A LOOK AT THIS VIDEO.....

 

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I removed one of the washer or "shims" from mine a couple years ago and was within acceptable tolerance for gap, also made sure was able to cycle properly. Also cleaned the surface of the clutch plate w/ some QD electrical cleaner while I was looking at it.

If I remember right just turn ignition on, toggle the dial for air to ac mode and back off should be able to make out an audible click of the clutch engaging. Mine got to where I would have to tap it to engage... or hit a good bump on the road if it had cycled off. If it is engaging fine but still same symptoms I'd look deeper.
 
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