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  #1  
Old 06-19-2006, 03:47 PM
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Question a/c quits cooling

Hi all! I have a 2002 F250 with 60k.My problem is the a/c quits cooling every now and then.Then the only way to get it started back is to shut the truck off for awhile.I checked and its full of R134a.Found no shorts in the wiring so far.Any help would be great! Thanks
 
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Old 06-19-2006, 05:19 PM
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Check your low presure switch.
You may have a weak a/c cluch, and when it get's hot it slips.
 
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Old 06-19-2006, 06:14 PM
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...Welcome Charles, to Ford Truck Enthusiasts!

See you on the boards. ….
 
  #4  
Old 06-19-2006, 08:04 PM
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Welcome. first dont shut her off anymore. Leave her run and see if the clutch engages. What happens is the magnetic field may get weak and wont pull it down. To fix this you need to pull the bolt out of the middle and remove a shim. This will bring the clutch ring closer to the ac pulley and allow engagement. Ive done it twice in 430k miles.
 
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Old 06-19-2006, 10:41 PM
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Replace your orifice tube, takes 3 minutes and $3.00. It may cost you a little more to recharge the system.

I had a similar problem. Fluxuating pressures, clutch kicking in and out whenever it wanted to. I discharged the system and pulled the orifice tube. There was a little bit of metal shaving at the larger end. I have been assured that although the metal shavings are normal, it only takes a very little to start reducing flow. So I replaced it, recharged it and all is great.

If you have gauges and a tank of 134A here's some stuff.
Low side should read 35-41 psi @ Idle
High side should read 195-201 @ Idle
Low @ 2000 rpm 30-32
High @ 2000 rpm 200-225
These readings are best taken at 72 degrees. If it is warmer out, or humid the readings will be slightly higher.

After discharge, remove black clip from tube coming out of firewall next to the canister.
You will need the proper tool to unseat the clip within the tube - AC Orifice tube removal tool, same as the fuel line disconnect tool.
Pull the orifice tube out with needle nose pliers and inspect for debris. Put the new one in RED SIDE toward the cab. Reconnect the tubes, install clip and recharge.

We thought it was electrical, low/high charge, clutch, switches...the whole shabang. Then the quiet guy mentioned something about an orifice tube. This dude needs to speak up more, he could save us some cash.
 
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Old 06-19-2006, 11:12 PM
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I have to ask: I have a 2002 as well, F-350 Lariat
My truck the other week or so, I was using the A/C on the MAX COOL setting, and the A/C just stopped, fan was blowing, but no air or anything, then it just came back, happened for about a minute or so
any ideas? it was on May 27th, just under 1 month, hasn't happened again, yet
 
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Old 06-19-2006, 11:13 PM
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You can test clogged orifice by hooking up gauges.
Low suction pressure at higher rpm would indicate it.
On my truck the pressure switch had bad connections. Some cleaning and bending the connectors fixed it.
 
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Old 06-20-2006, 08:07 AM
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Originally Posted by toyota hauler
I have to ask: I have a 2002 as well, F-350 Lariat
My truck the other week or so, I was using the A/C on the MAX COOL setting, and the A/C just stopped, fan was blowing, but no air or anything, then it just came back, happened for about a minute or so
any ideas? it was on May 27th, just under 1 month, hasn't happened again, yet
The suspect could be the vac pump, vac lines. Seems like the internal doors in the HVAC system are opening and shutting at will.
 
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Old 06-20-2006, 01:25 PM
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Thanks for the advise all!
 
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Old 06-20-2006, 04:08 PM
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Check with your local dealer.... there was a TSB (technical service bulletin) published for this exact issue. There is air in your refrigerant system and they will evacuate it and recharge your A/C system. If I can find it I will post the TSB bulletin #. If I remember correctly the 02-03 production years were effected.
 
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Old 06-20-2006, 04:42 PM
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The problem could also be caused by a bad WOT relay. To verify this, the next time the AC stops, floor the accelerator for a few seconds, then come back to idle and see if your AC starts working again.
 

Last edited by Bob Ayers; 06-20-2006 at 04:44 PM.
  #12  
Old 06-20-2006, 11:13 PM
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my truck was def just idling when it happened
 
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Old 06-21-2006, 05:26 AM
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Originally Posted by kennedyford
Welcome. first dont shut her off anymore. Leave her run and see if the clutch engages. What happens is the magnetic field may get weak and wont pull it down. To fix this you need to pull the bolt out of the middle and remove a shim. This will bring the clutch ring closer to the ac pulley and allow engagement. Ive done it twice in 430k miles.
Same exact thing happened to me at 268k..Trust me, if it's the clutch it's an easy fix.
 
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Old 06-21-2006, 12:21 PM
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I read a post where a guy with 430,000 miles on his truck has twice had to pull shims out of the clutch to make it work again.
 




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