How do I adjust the AC Compressors Cycling? Where is the screw to adjust it? Front, Back, Left Front??? I own an 86 SC and converted it over to 134 A and could not find any screw hole. Also is it phillips or regular?

 

I don't think there is one.. What makes u think there is. just curious if maybe other cars have em.. I know home A\C units do..

 

well i just fixed my a/c, just needed one can of r-12 to make me freeze in 90 degree weather.

this should cover most of what u need.

https://www.thirdgen.org/newdesign/t...trofitac.shtml

 

i learn something new daily. now i just wish i had a working a\c

 

Typically a compressor cycling off and on frequently is a sign of low coolant level...not enough R-12 or R-134 if you have made the switch. There should not be an adjustment screw....it is dependant on pressure in the system and sometimes, if coolant is too low, it could also freeze up the system causing a shutdown till it defrosts....(cause of pressure)

 

I know about the Compressor, the Condenser, the Blower motor, the Condenser coil, but where is this screw that needs adjustment to 21psi???? Anyone have a digital pic of it. My Hayes Manual and Chilton’s make no reference to it and overall suck on AC info…

 

I think thats what everyone has been saying, THERE IS NO SCREW on the A/C system to adjust, there is a preset pressure switch on the accumulator that controls the compressor when the pressure in the system drops too far. but that is not adjustable.

 

go get your system charged to the proper level and it should stop cycling so often.....

 

the screw is on the plug going into the accumulator. just pull it off and u will see it between the terminals. 134a operates at different pressure than r12, which the system was designed for, so its ok to adjust a little to keep it from cycling.

 

There is a small flathead screw between the terminals of most cycling switches, that is located on the accumulator. I wouldn't adjust it down to 21psi though. Adjust it so the off time is 6-12
seconds or so, that should be about right.

 

Anyone with a digital pick? What is the accumulator?

 

anyone? My hayes and chiltons are useless...

 

the accumulator is the big silver thing mounted on the firewall on the passenger side of the bay. there is a cooling line comming from it, should be between the engine and the heater fan motor.

 

My AC is NOT cycling.....

The compressor was replaced by a used one (I had nothing to do with this and it was done free by my fiance's mom's boyfriend) as hers in the '91 RS had died. Actually, the air hadn't worked at all since she had the car.

Anyway, she said it worked great at first then a few days later I go to drive the car after she drove it down from VA to Savannah and the air is cycling on and off and not really cold.

I buy one of those cheap Interdynamics charge and fill kits (he had put a 134A fitting on the dryer) and put the little guage on the low side and per instructions check the pressure, which if I am correct should be "suction?" and anyhow it's in the low zone at 20 or so. So I hook up a can of 134A with leak sealant in it and turn it on. I had to jump out the pressure switch on the dryer as it had too little freon in it to kick in. I let it suck in the can, the air blows cold now, but with the switch re connected it does not cycle on and off. I re-connected the little gauge and it shows it to be in the "good" zone on charge, which is green on the gauge.
Could I have a bad pressure swich? I know there is a leak somewhere, but as long as I can throw a $4.00 can of 134 in it every week or so I don't care as long as it gets through the summer!

 

If the compressor is cycling, then you usually need to add coolant--134 will work fine. The other thing that could cause cycling is if the A/C system has been worked on and someone put too much oil in.