Recharged A/C -- Compressor on/off rapidly - not cooling

[thgood]

I just charged the A/C system on my 94 explorer --
it was already the R-34A system.

Before I charged, the compressor did not switch on at all.

I hooked up the recharge kit -- it took about 3/4 of a can. Now the AC kicks on for about 1 second, then switches off -- it keeps doing that cycle.

Low side varies between 25 to 50 psi --
High side varies between 150 to 200 psi --

Each does this every compressor cycle -- I belive it is supposed to hold pressure more constantly.
I don't think it is a leak though because it holds the pressure when the car is off.

Any Ideas?

Tom

 

[2001ExpSport]

Was the system empty when you started?

From what I understand, you need to add 134 until the compressor stays on constant. When the a/c gets up to temp the compressor will shut off. When it gets enough 134 it will stabilize between 35 and 45 psi on the low side. My friend's 5.0 X runs between 35 and 45psi. It will compress up to 45 then down to 35 then back up tp 45 and so on back and forth. Basically, cycling the 134. For some reason, mine never did that before I broke a hose.

There's a sticker above the radiator that tells you how much 134 you need. My OHC requires 1 lb 14 oz plus 9 oz of oil(39 oz total). I've found that if you over fill the system, it will run for a while and then shut off when the low side jumps to about 150psi. The techs I talked to said that more is not better. I have tried all week to stabilize my system. I am taking it to the shop tomorrow. I don't feel like messing around anymore.

Well, I hope some of this helps.

Try here too...
A/C Info

 

[thgood]

Fixed problem

The system was not lubricated enough -- I bought the 2 oz ester oil can and added that to the system. Now the compressor stays on.

I read some other posts and saw that a fast cycling clutch can burn out really quickly... My compressor / cluch had not run for at least a year -- so my advice would be to add the ester first if you are in a similar situation.

The a/c compressor still sounds a little loud. The parts guy recommended I add another ester oil can to the system, any comments?

 

[2001ExpSport]

Had mine fixed yesterday, it was low. Everything runs fin now. Oil is nothing going to cause the compressor to kick on and off. That can also has 2 oz of coolant. You added 4 oz. You were probably low. The compressor is regulated but a high and low pressure switch. If you were low, the low pressure would turn the compressor off shortly after it went on due to low pressure. If it stays on now, I would not add any more. In cooler temps the compressor will not stay on all the time.