[jmann]

My a/c id not working properly - hot air comes out at times. I looked under hood and see we take the new type of coolant that you can recharge yourself. As I happen to have some with the qage on it, I figured I would check/refill it. I looked under hood and there appears to be two valves: one on the left side (looking at enging from the front) near the firewall and one on right side near the radiator. Both valves seem to look the same and neither is labled. They both are part of cooling system. The one on left side into black box and the one on right goes to a line into compressor. which one to I hook the charging unit up to? Also any ideas what else besides coolant could be the problem? I see no leaks in system and it worked fine last summer. Thanks

 

[jmann]

Ok, after doing some more research, I found that the orifice near blower on left side is the low pressure and the one on right side is high pressure. From what I have seen, the low should be charged to 45 and high to like 275. Do I test them with engine on and ac running or when off? Also, how do I check the heater core to make sure that it is clean? Is it behind the glove box and accessed from cab or so I access it from under the hood? Dang manuals do not say.

 

[fourhatz]

Your pressures will depend on the ambient air temp and humidity. The pressures you state would be taken while the truck is running, as when it is not running the pressures will stabalize and read equal. Charging the A/C as you are, you want to put it in on the low side while the compressor is cycling. This will allow it to suck the freon in.

 

[tallfarmboy]

To check your heater/cooling fins, simply remove the 4 screws holding your blower motor into its housing, then pop the fan out (remove electrical connector first) and you'll see the fins down inside the housing.

Flush out with some clean water and some have been using a coil cleaner made for AC coils to clean them..

Good luck,

TFB

 

[jmann]

Thanks, as it turned out, the refill gage and tank that I hadwas broken ( should not have tossed it in the tool box) so I took it to Big O and they checked it and said there were no leaks, but the comp clutch was out as they could not get the correct pressures. I priced a compr and it looks like around $169 with the clutch at checker. Is there any trick to replacing the thing short of depressuring the system before doing it? It looks like there is a bolt on back of compresser that you undo to detatch hoses. Any other tricks from anyone who has done one? Any easy way to relieve pressure if I need to do that? Thanks again for the help.

 

[72Pstroke]

If you are going to replace your compressor, you may be better off to let someone do it. There are a lot of requirements you need to meet for the warranty to be honored, and it is almost impossible to prove everything was done right if you have compressor trouble later on, unless you have a shop invoice with all the work written on it. They will require you to change the accumulator, and the system will have to be flushed and re-oiled. You probably will want to clean the orifice tube while you're at it. You will have to evacuate the system before you remove the compressor, and it will need to have a vacuum pulled on it before you reinstall the R-134. It also seems that rebuilt compressors are hit or miss any more, so there is a pretty good chance you will need your warranty.
Tim

 

[mrvmax1]

It can be done yourself if you have the time. The materials needed are fairly cheap. You can do a better job than the shop at much less. I'd just be sure that they will honor the warranty if you do it.

 

[jmann]

Thanks for the info - prob a good plan re warranty. I read in some posts that cleaning the heater core can make a difference, so I decided to try it in hopes of getting a little cold till I can get compresser swapped out. Well, I took off the washer fluid res, unplugged the electricals and took out the blower motor. I took the garden hose and sprayed the hell out of the core and all kinds of crap came out - prob 10 years of dust, bugs and leaves. I put her back together and tried a/c and it blows cold as a fridge now. I test drove it and it blows cold at idle and speed. Now, I do not know if the shop just refilled the coolant and saw that it ran hot with no leaks and just assumed the compresser was bad or what, but it is as cold as I have ever seen an a/c and it was near 100 today in Utah! If your a/c seems warmer lately, try cleaning the core out and you may be pleasantly surprised like I am.