92's AC done for? Help?

[BrianDye]

When I got my 92, the AC blew out not room temp, but a little less, kinda cold I guess, so I recharged it, it was sooo low, on my tester gauge it was all the way down almost, but anyways, it was blowing out ICE COLD for about 2 months, then I noticed it started blowing out COLD but not ICE COLD like it was, and then I noticed that it would go from ice cold, to kinda cold, then if I floored it for a sec, or revved the engine it would get ICE cold again.

Then the last week or 2 its just been how it was before I recharged it, literally its nicer to have the windows down on a 90* day otherwise its just like having room temp. air blown at you. When I move the lever to MAX AC, and press the knob in to turn AC on, thats how I always kept it, now when its on, theres a constant clicking noise coming from the engine, and when I turn the AC off it stops.

I checked the pressure today, and its still around 40-45 where it should be, but no cold air!


Any suggestions? Is there something I need to replace?

 

[Maniak]

It is the difference in pressures that make it cold.

Are you using one of those single gauge things? or a full manifold set?

Using a full manifold set you need the static pressure (before you turn on the a/c), ambient temp and then turn on the a/c and get the high and low pressures..

~Mark

 

[cybergasm]

Could be the Clutch on the Compressor is starting to slip. or the low pressure switch is kicking the compressor on and off in a rapid fashion.

i would bypass the switch and see if the noise goes away if it does then freon is too low in the system.

if it remains then clutch is going out on the compressor.

good luck

 

[BrianDye]

Its just one of the gauges you check with the truck running, ac on full blast, its in the high green level, like 40-45 I think it was saying, how do I check the static pressure, or what you were saying todo...?

Im pretty sure the compresser is runing, because when i actually click the AC on it does get noticeably colder

 

[marragtop]

You need to use a proper set of gauges. It sounds like you are low on freon, but you cant keep dumping freon in without properly measuring the pressures. Do you have an R12 or R134 system? If R12, you should consider converting to 134.

 

[Anime]

I'd say it's low on freon.

My X has done the same thing for years. When I finally had it recharged again last year(with genuine DuPont R-12), it was completely empty, took two 1 lb cans. Now it's slowly blowing warmer air.

My guess is the hoses, fittings, or just the overall system design isn't all that leakproof, or it requires more maintenance in terms of replacing fittings, hoses, or other leak points.

Given the extremely high cost of freon these days (~$80/lb), I'd say it's a LOT less expensive in the long run to just do a complete R-134a conversion, with new barrier hoses, fittings, evaporator, the works. It's about the same to convert as it is to get two cans and pay any evac/recovery fees. After that, you're only saving money for any cans of R-134a you get instead of continually forking out for more R-12 on a leaky system.

 

[BrianDye]

It was converted a longgg time ago, but why would it say I have almost too much freon, compared to being low?

Where can I get a "real" gauge set?

 

[Maniak]

Do you have Harbor Freight tools around there? The Manifold set sells for $39 to $69 (depending on sales/coupons).

btw.. static pressure is what pressure you have before you turn on the a/c (it needs to have been off for at least 10 minutes, maybe a little longer).

edit: here it is.. I always print out the pages and take it in.. that way if the 'net price is cheaper I can get it.. At least every time I showed them the paper they gave me the 'net price. http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92649

~Mark

 

[BrianDye]

Nope, we just have Napa, Autozone, Murrays, and Advance....Autozone rents tools for free, do you think they'd have it?


Can I check the static with the gauge I have?

 

[Maniak]

HarborFreight is a tool store (cheap tools).. yes, some autoparts stores have them, but it'll cost more than it would at harborfreight.

Yes, the single gauge should give you accurate static pressure.

~Mark

 

[BrianDye]

Ive been home for about an hour now, NO ac, so how do I check the static pressure? Truck running or no?

 

[Maniak]

You don't even need to start the truck, just hook up the gauge and get the reading.. it should be about the same as the ambient temperature...

for example, if its 90F outside, you should see 90 psi.

You really need to get a full manifold set, as we need to see the high/low pressure relationship when the system is on too.

~Mark

 

[BrianDye]

With the truck running, ac off it reads about 100 PSI, I didnt get to check it with the truck off yet, maybe later when I get home I can.

What exactly does the manifold set do?
I seen it at AutoZone for 54.99$ if it would really help I could buy it, keep it clean when I use it, then take it back lol

 

[Maniak]

How hot was it there? At 100psi that means it should be about 100F right at the condensor.. If its not that hot, you may have too much r-134 in the system.. its hard to telll..

A manifold gauge will show you the high and low pressure at the same time.. Using those, you can get a better idea if the compressor is working, you have a blockage, or are low on r-134..

You also use the manifold set to act as the connection to the vacuum pump when you need to evacuate the system and to charge the system. BTW.. Autozone (at least around here) rents out the vacuum pump so you can evacuate the system yourself.

There are some good threads in the a/c section of this forum.. may be worth a reard about hwo the a/c work.. it will help clear things up some

~Mark

 

[BrianDye]

Well im not sure it was 100 out today but I know it was damn close if you were out in the sun, but yeah I meant to ask today when I was there if they rented the manifold gauges.

I really appreciate all the help and information, like you said it may be too high....On the gauge I have theres like green which is normal, yellow which means caution, red means warning, and another higher step, mines in the yellow...