A/C Help

Performance modifications, tips & tricks

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z71gmc06
Posts: 1013
Joined: Tue May 08, 2007 12:45 pm
Location: Michigan

A/C Help

Post by z71gmc06 »

So I have been having this ongoing problem with my AC since last year. It starts up fine and is nice and cool, but then after 10-15 minutes it cycles off and then won't come on again till I shut the truck off and restart.

I have determined that the compressor is just not engaging when the truck is blowing hot air

Last summer I checked the freon with one of those cheap guages that comes on a bottle and it was fine, but the problem remained.

This summer I put in a new compressor relay - not it!

This morning I drove the truck for awhile and got it to fail, then Jumpered low pressure switch - not it either.

So just out of curiosity I tapped the front of the compressor clutch with a hammer and lo and behold it snapped right in and started to work. So now I have been researching online and have seen a few references to adjusting the gap on the clutch.

My question is: can this be done on my year 2006 GMC? And how do I do it? Or am I just better off replacing the whole thing now since I have over 150,000 miles on it?

Thanks, Dave

Whipped383
Posts: 2104
Joined: Mon Mar 01, 2010 9:12 pm
Location: Salt Lake, 97K1500,ECSB, 383,Whipple,0411,Marine, 03K2500,CCSB,8.1&Allison, Whipple in progress

Post by Whipped383 »

Most of the time you can pull the bolt out of the center of the clutch and the front plate will slide off and there may or may not be shims behind it. Im not sure if yout compressor will be that way or not but its worth a shot anyway

Chevy 97
Posts: 1077
Joined: Tue Jan 24, 2012 1:19 pm
Location: 97 ECSB K1500 6.3L 4L80E 14 bolt SF Hydro Boost, Headman Ellite Headers, 140 amp alt.

Post by Chevy 97 »

Check to make sure the magnet doesn't have some thing wrong. You actually need both gauges in at the same time to see how the A/C system is working properly. I have to check mine out this year, hasn't been done for a couple of years. I have never had the R 134a out of my A/C system. It seams to take longer to cool off them before. Maybe low. I can check that at work on the new A/C machine. I just have to find out how much my system needs to fill it. That information was removed when the truck had front end damage. They never replaced the sticker that tells that information. I better get back to bed have to get up in two hours. Work is getting in my way of home time....LOL...

z71gmc06
Posts: 1013
Joined: Tue May 08, 2007 12:45 pm
Location: Michigan

Post by z71gmc06 »

Thanks for the reply's guys.

I will investigate further on the type of compressor.

I know that I should have two guages to check the pressure properly, but I'm pretty sure that is not the problem in this case.

when the compressor is running it cools fine.

I sprayed wd 40 on the clutch and it's working fine for now, so maybe it will buy me some time to find out more. I read somewhere that there are some tools to allow you to press the clutch together a little more and I read about the shims. Now I just need to figure out which type I have.

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