A/C compressor bad?

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
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Arkansas
Well every year I have struggled with the heat/humidity in AR. I don't really know why it doesn't blow very cold. I went last fall to a a/c shop and he said it had been converted over to R134a. Well the vent temps at idle were like 82* or something like that if I recall:nono:

He put all his guages on/etc...he said it was fully charged. He didn't know why it would be bad...what are you guys thoughts on that?

Is the compressor not working right or something?

Any ideas...

Thanks:nice:

Also, how much does a compressor cost?
 
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Have someone turn the A/C on while you watch the compressor, you'll know if the clutch engages.

You have to be careful with 134 in our cars, that stuff eats compressors for breakfast. It runs at higher pressure and eventually blows the seals out. Usually works fine for a year, then goes down hill. I think it also needs better O rings.

A new dryer may also help if that wasn't replaced when whoever converted it, so would a better electric fan, like the lincoln or the 94/95, they have much more of a shroud and suck the air through better than the BM.

The only old foxes i've been in with properly working A/C either still had r112 or all had very powerful electric fans.

Search Jrickers pages, i think he had a nice write up on the A/C conversion.
 
I know the clutch engages, but is it doing it efficiently or 100%...that's the question.

I do plan on getting a new fan upgrade and all that sometime, hopefully soon...but the a/c still doesn't blow good even on the i-state and I have a good radiator that cools great.
 
as for the clutch, there's a few things that can cause it to not cylce properly. first off, you said it's kicking on......is it staying on or is it on and off alot??

there's a sensor somewhere in the system that tells it when to cycle, it will cycle on and off too much if it's low on freon ( which you said was checked) and, there is a full throttle switch that dis enguages the ac on full throttle. those can go bad causing it to cycle funny or not come on at all. it is a relay located over by the maf meter, mine went bad last year, i also needed new lines as well..

if the clucth is coming on and staying on and it still just doesnt feel cool, i have heard sometimes they really need to cycle the compressor alot on the dryer machine to get any moisture or air out, matter of fact i think jrichker has a real good write up on 134a systems.

i had the guys who did my a/c say flat out 134a doesn't cool as well.....i stuck with the r-12, but, even if it doesn't cool as well it should cool well enough that it doesn't seem like somethings wrong......after all, all the new stuff uses it......
 
timewarped1972 said:
as for the clutch, there's a few things that can cause it to not cylce properly. first off, you said it's kicking on......is it staying on or is it on and off alot??

there's a sensor somewhere in the system that tells it when to cycle, it will cycle on and off too much if it's low on freon ( which you said was checked) and, there is a full throttle switch that dis enguages the ac on full throttle. those can go bad causing it to cycle funny or not come on at all. it is a relay located over by the maf meter, mine went bad last year, i also needed new lines as well..

if the clucth is coming on and staying on and it still just doesnt feel cool, i have heard sometimes they really need to cycle the compressor alot on the dryer machine to get any moisture or air out, matter of fact i think jrichker has a real good write up on 134a systems.

i had the guys who did my a/c say flat out 134a doesn't cool as well.....i stuck with the r-12, but, even if it doesn't cool as well it should cool well enough that it doesn't seem like somethings wrong......after all, all the new stuff uses it......

Well currently my car isn't running...going to pick-up my block later next week to start putting it back together...

If I recall correctly, it would kick on every 10-15 seconds, and just for a few seconds at a time at idle.

Yeah, I know r12 cools better...but like you said, all the new "stuff" uses it...:shrug:
 
Need to know what the pressures where when it was checked. I could be a number of items as stated above. The Fox style compressor didn't not always work well when they where converted, especially if it was converted back in the early to mid 90s when they first started to do that. Most;y because the conversions where not being done correctly by most people.

My guess is that it is a relay or switch if its not cycling properly. But it could be that the 134a has ate away at the o-rings and is causing a restriction in the line somewhere. Take it to a good AC shop, Arkansas Auto Air in Little Rock is good, I have used them in the past. But now I have all my own AC gear. So if you need a recharge or vacum???

As a side not. I use to install Home AC for a living.
 
92importkiller - I live 45 minutes northwest of Little Rock in a town called Perryville. You?

backfocus - Thanks man, just roughly where about is the arkansas auto air located at in LR? I tried looking in the yellow pages to no avail:shrug:
 
From the symptoms (pressures okay, yet cycles a lot), my first guess is a restriction at the orifice. This is the most common part to become clogged.

Another common issue with the Fox are the 4 wires at the WOT relay. This is a small rectangular plastic box that is mounted on the front side of the passenger shock tower. The insulation burns and shorts out the relay. They are ~17 from Ford. Plus, when they short out, they sometimes take out the LPCS (Low Pressure Cycling Switch). This is the switch that turns off the system when the low side gets to a certain point. For R12, it is set to 25PSI. For an R134A conversion, it is usually adjusted to around 18 or 19 to get the best vent temp. This switch can also go bad. It is ~$30 from Ford last time I bought one.

Also, R134A ends up being at an 80-85% charge of R12. I have no idea what the A/C shop is determining it to be properly charged.

For a more in-depth look on how to convert, see the URL below.

http://www.knology.net/~puter/carpics/r134a.html