1999 F250 Hard to diagnose AC when it works fine 98% of the time. Blows real cold air. But, then like today when it's almost 95 out it was blowing cold air then just started blowing HOT air... Usually after a few minutes or shut her off and the next time you get in it's blowing cold again?

Any thoughts?

It's been 4 years since I had the AC serivcied by Ford...

 

I want to thank SpringerPop's fix for the Compressor Clutch Air Gap.
I have struggled with no AC for two years and was reading these posts. The description fit mine. AC blows cold for a while, hit abump, idle or pull trailer it begins to blow hot air. Before a completefailure, sometimes you get cold air and sometimes not.

My son in law performed the FIX, parts cost me $1.99 (Autozone MT0986) and 15 minutes later it is working like a champ!!


The compressor clutch has becomeintermittent. The electromagnetic coil that pulls in the clutch plate can nolonger do its job and the AC no longer comes on resulting in no cold air. <o></o>

Try this to test: <o></o>

Turn on the A/C and run it until theclutch won't re-engage. Be REAL CAREFUL now! Take a plastic screwdriver handleand "tap" the end of the (not spinning) clutch. Does it immediatelyengage and operate normally until it next cycles off, and then won't re-engageon its own? <o></o>

If so: <o></o>

Remove the clutch plate: Turn theignition to ON (do not start) and be sure the AC is turned to the ON positiontoo. This pulls in the clutch so that the serpentine belt holds it all fromturning. <o></o>

Turn off the AC switch and ignitionswitch. The air gap will reappear. Carefully slide the clutch plate forward. Becareful to not drop any shims. There may be more than one and could be stuck tothe end of the compressor shaft or down inside the splines of the clutch plate.Remove and measure the thickness.<o></o>

Get out your feeler gauges, or yourcalibrated eyeballs, and determine that the air gap is about .050" to.060" (fifty or sixty thousandths). That's too much! It's supposed to bearound .030. But wait! There's no need to replace the compressor and have tore-charge the system. There's a "dirt-cheap" fix! <o></o>

See the little bolt right in themiddle of the compressor shaft? Take it out. You won't be letting any Freonout. Pull the clutch plate straight out. There is one or more "shims"that look like small washers in there, either on the end of the shaft or downin the hole that fits on the shaft. Take off about .030" worth of them andreassemble. Go ahead; use a little blue (NOT green!) Loctite on the bolt asinsurance.

Make sure you now have at least.025" of gap. Start the engine and check to insure your problem is gone.<o></o>

Just be sure to not take ALL thespacer shims out (unless it's necessary), as the clutch MUST have some air gap.<o></o>

It HAS to be able to cycle on and off.<o></o>

If it has NO air gap, it won't cycleoff, and WILL damage the compressor by over-pressurizing the high side.

I hope this helps someone else in saving money and getting their equipment working.
2004 Ford F250 6.0 Diesel


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Hey guys, been having difficulty trying to investigate why my A/C unit is having problems blowing cold air etc. Steps I took :vac system recharge system with recommended numbers; pressures are good holding steady on gauges etc., and blowing cold air. The very next morning A/C blowing hot air compressor dose not engage and I am pissed does any of you guys have a clue what is happening with my A/C unit. Thanks

 

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