AC thermostat problem

[zoe60]

I'm messing with my '89's air conditioner. It works but it cycles on and off too much so it never gets cool enough. I traced it to this thermostat thing. I wonder if anything can be done with it. If I short the two wires the compressor stays on and the car gets cold as a witches you know what. I know some of you are good with the AC on festys. I could keep the wires hooked together but it will probably screw up my compressor. Thanks.

[muddevil01]

Usually if the compressor cycles on and off it's due being low on freon and if you force it to run it will destroy the compressor

[Movin]

The AC clutch cycling switch wears out on these. They can be adjusted
but they usually don't stay adjusted long once they reach this stage.
Mark where the teeny screws are set and make a small adjustment
with AC on. Don't make it too cold, they will work really well for a bit
then ice up and blow warm. About 38 deg should work.

A new ac clutch cycling switch is under $30

If your AC does not get cold with clutch bypassed then yes, it may
just be low on freon.

What the heck!!??? its 19 and snowey !!!!

[zoe60]

I had an AC shop put R12 in it last summer. it was just barely low when I had it put in. It has always done this regardless of freon charge. The guys at the AC place were surprised at how good condition it is in. I think the recycling switch is bad. How hard is it to replace? Where are the adjusting screws? Where can I get a new one?
Yeah it's cold here too. I got bored and got a wild hair to mess with it. I'll be ready for summer though!

[zoe60]

Does anyone know by the picture if my AC is factory or dealer add on? I found one but I want to be sure it's the right one. Thanks Movin!

[Movin]

That looks factory. they are not bad, it only takes about an hour
to pull the evaporator and you do not need to go that far.
Don't be afraid to mess with your old one.
A new one will look different, they all do the same thing, temp
senser in evaporator fins, turn off compressor when cold enough
turn it back on when when warm.
The fast cycling does not apply to festies and low charge, those are
pressure cycled systems. festies will slow cycle when low. The pressure
switch is high pressure cut.

[zoe60]

I got it adjusted tonight. Kicks off around 38 degrees like you said. Had to adjust the little screw a long ways. I think if the freon was low the pressure switch would shut it down. I'll bet you are right about it not staying adjusted for long. hope I can find a new one. I guess it's the switch itself and not the orifice tube and all that. That would be somewhat of a pain to replace. Anyway, thanks for the help!

[FestYboy]

where are you getting R12!?! that's no longer used on anything other than certain comercial refer systems. at any rate, don't open the system if you can avoid it. r12 is awefull expensive and hard to find (hasn't been produced in almost 20 years). if you open the system for repairs, flush with alcahol and refit for r-134.

[Movin]

I still have more than 30 lbs.. I use a lot of 134 but some of the hybrid stuff
cools better than either 134 or 12, is easier on compressors, mixes with all
compressor oil, does not burn or explode and is about the same as 134 price
wise. I use the 50 lb tanks. It is a popular choice..

[zoe60]

I just went to an air conditioning place here in town and they still had it last year. It is expensive though. I think they ended up putting in a half pound for about 120.00. I figure if it was designed to run with it I should try to use it. I may convert it someday, but for now I'm gonna keep it like it is. I baby this old car too much.

[FestYboy]

8oz. for $120!!! holy carp!

Movin's onto somethin with the hybrid coolent, it's better than the 134 and about the same price too AND you can buy it (can't buy r12, at least not NEW r12, illegal, like VERY illegal if you don't have you certs in HAVC and the fed license)

[zoe60]

Yeah, I know, but it doesn't leak so hopefully I won't have to do it again for a while. Some of that was labor too. I think it was the first time it has ever been serviced, so 8 oz. over 23 years ain't too bad.

[Movin]

Yes, you have to keep copies of license and certs at the distributor here.
Plus all the MSDS on site. Plus file map of site with locations of chemicals to
to the city and the state. And study/semenar like crazy to keep up with technology.

There are several kinds out there but avoid ones that can burn, a little flammable
material will carry oil and not burn but some use too much. Probably because they
can't copy each other.

[navdoc101]

The AC clutch cycling switch wears out on these. They can be adjusted
but they usually don't stay adjusted long once they reach this stage.
Mark where the teeny screws are set and make a small adjustment
with AC on. Don't make it too cold, they will work really well for a bit
then ice up and blow warm. About 38 deg should work.

A new ac clutch cycling switch is under $30

If your AC does not get cold with clutch bypassed then yes, it may
just be low on freon.

What the heck!!??? its 19 and snowey !!!!

Just where is the a/c clutch cycling switch located. I'm gonna tryto adjust it. Thanks,Gary

[zoe60]

If you take out your glove compartment it is a lot easier. Look at the black plastic box and it is mounted on the lower left. Remove the two screws and pull the adjuster cable out of it's clamp. be careful not to break the tube and you can bend it around. there is a little screw on the back. I turned mine to the left several turns. Run the AC and hold a thermometer in front of the vents. try to get it to where the compressor turns off at 38 degrees like Movin said. The poition of the thermostat lever affects it too so make sure the little lever is all the way cold. When I got done I dabbed a little 5 minute epoxy on the screw so it woul stay put. Hope yours works as well as mine!