A.C. problem

[Keith Richards]

Anyone experience a.c. problems with their trucks? Mine has been blowing hot air.I had it at a shop recently for some brake pads and told the guy to fix it, as soon as I got in the truck I noticed its still blowing hot air.I told the "competant"? mechanic and he said he filled it up,like he didnt understand the problem.I filled it up myself recently,to no avail.I used the new stuff ,not freon.Is it supposed to have freon?Any help is greatly appreciated,as always.Theres nothing like working all day long in the hot sun,and getting in a truck that blows hot air.

[rjschoolcraft]

First, see if the compressor clutch is engaging. Then, if it is, have the system pressures checked. If the clutch isn't engaging, it could be an electrical problem or lack of refrigerant. Your 98 should use the R134a.

[Keith Richards]

Thanks ronniejoe,yes the mechanic says he checked pressure,and I'm using the proper refridgerant.I'll try checking if its clicking on or not.Unfortunately I'll probably have to bring it back to the guy.If it's electical im out.The heat kicks.The heat and ac has given me alot of headaches with this truck.I've had to replace the whole heat/ac panel only to find a burnt coupling behind the knob that contols the fan power.Sometimes it would just cut out.Now only the third and fourth(full blast)works.I never have time to put the truck down at a mechanic because I'm a contractor and constantly using it.frustrating,but at least it runs strong.

[Keith Richards]

By the way,how do I know if the compressor clutch is working?All I know is I can hear a slight inrease/decrease in RPM when turned on or off.

[rjschoolcraft]

Look at it with the hood up and see if the center section is turning with the pulley.

[DickWells]

Take the two wire connecter off the expansion tank at the firewall on the passenger side and jumper the two wires together while the engine is running. If the cercuits are complete, you'll see and here the AC clutch kick in. I think your's is working from what you said about being able to here and feel it from the driver's seat, but it's worth jumping those two wires just to prove it.
Beyond that, I have nothing to offer. In fact, my 95 Astro Van's AC isn't working right now, and I haven't been able to find the problem. I think it boils down to the controls in my case.
Good luck.
Dick

[Dihrdbowti]

You might want to go to a dedicated AC shop. I just had my 96 in to the AC shop. It would blow warm for about 10 minutes then all of a sudden it would start blowing cold. the problem was the cycle switch. It is the switch on the cylindrical thing (sorry don't know the technical name maybe accumulator?), up on the passenger side firewall. $18 for the switch and $32 for labor. Now works like a champ. Wished I had the old R12 got real cold real fast. Seems like 134R takes a little longer to get there.

[DickWells]

Whoops Fellas! See and here the clutch engage?
My gosh, I'm getting worse all the time. I meant ("see and hear"). I just love this getting old. Can't even remember to proof-read what I've written. Oh well, you probably knew what I meant.
Hope your AC problems have been solved by now.
Dick Wells