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AC doesn't work.. common problems?

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Old 06-13-2010, 06:13 PM
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Default AC doesn't work.. common problems?

What generally happens with the ac in these? Compressor goes bad? Does it just need a recharge? How do I diagnose something like this?

Matt
 
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Old 06-13-2010, 08:40 PM
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Is the compressor locked up? Does it have any charge in it at all? If the compressor isn't locked up and its got some charge in it I would say it just bled down and needs a shot of freon in it.
 
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Old 06-13-2010, 08:48 PM
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Could be a bad compressor as stated already...
OR...
Anything line related,accumulator and/or the evaporator core.

I'd bet money on the evap core being bad,its a well known problem on all the 2nd Gen's.
If you do the repair on it make sure while your in there to do the heater core,its a no brainer.
 
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Old 06-13-2010, 10:42 PM
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Try recharging it, easy to do yourself. Buy 2-3 cans, it may suck down the first with out coming on. If it won't take any your system may have lost it's vacuum and it takes a setup I don't have to regain that vacuum. You may need to add a can every spring when it gets warm enough to need the AC again.
 
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Old 06-13-2010, 11:40 PM
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i would have to say if you dont know about ac systems, pay someone who does. its just one of those things you need to know before messing with it. ive personally seen someone shread there hand from a freon bottle blowing up not charging it correctly
 
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Old 06-13-2010, 11:59 PM
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Originally Posted by tltruckparts
i would have to say if you dont know about ac systems, pay someone who does. its just one of those things you need to know before messing with it. ive personally seen someone shread there hand from a freon bottle blowing up not charging it correctly
x2 Besides just hurting yourself you can damage things like the compressor or other things if its not done right.
 
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Old 06-14-2010, 08:23 AM
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Originally Posted by 2MuchJunk
Is the compressor locked up? Does it have any charge in it at all? If the compressor isn't locked up and its got some charge in it I would say it just bled down and needs a shot of freon in it.
How do I tell if it's locked up? Try turning the pully?

Originally Posted by Hammer
Could be a bad compressor as stated already...
OR...
Anything line related,accumulator and/or the evaporator core.

I'd bet money on the evap core being bad,its a well known problem on all the 2nd Gen's.
If you do the repair on it make sure while your in there to do the heater core,its a no brainer.
Do I replace the evap core or is there a trick to do?

Originally Posted by tpcdrafting
Try recharging it, easy to do yourself. Buy 2-3 cans, it may suck down the first with out coming on. If it won't take any your system may have lost it's vacuum and it takes a setup I don't have to regain that vacuum. You may need to add a can every spring when it gets warm enough to need the AC again.
I may just try this too, sicne cans are cheap

Originally Posted by tltruckparts
i would have to say if you dont know about ac systems, pay someone who does. its just one of those things you need to know before messing with it. ive personally seen someone shread there hand from a freon bottle blowing up not charging it correctly
I've loaded freon cans up before. But thats prolly about as far as I've gone with ac besides replacing some nut in the evap of one of my cars. Paying people for sh*t is stupid though
 
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Old 06-14-2010, 10:46 AM
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Originally Posted by 85_305
How do I tell if it's locked up? Try turning the pully?



I've loaded freon cans up before. But thats prolly about as far as I've gone with ac besides replacing some nut in the evap of one of my cars. Paying people for sh*t is stupid though
you try to turn the clutch not the pulley

and loading up cans from oreilly or napa is not doing ac work. do it right, get a real manifold gauge on it, you need a vacuum pump to get the moisture out so itll work right and not freeze up. find a buddy or something that knows how to do it. but just do it the right way. i know your already aware of what happens to vehicles when you dont do things right. so go pay the 100 bucks and get it done its not that expensive. its probbaly cheaper in the long run compared to just keep throwing bottles of freon and guess work at it

also throwing bottles of freon at it is not a good idea if you dont know whats wrong. those crappy gauges that come with them never work right, and also it wont measure right until the compressor kicks on and its cycling. if you just keep loading freon into it without knowing what your high side pressure is you can hurt yourself, someone else, or your ac components. its not worth it
 
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Old 06-14-2010, 11:29 AM
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So it'd be about 100 bucks to diagnose/fix the ac? I see your point with everything else.
 
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Old 06-14-2010, 11:47 AM
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does the compressor clutch engauge when the in cab control in turned on? thats where you need to start. have the truck idle, turn the ac on, and look to see if the clutch enguages ( would be super easy with two people)
 


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