A New One

[nduncan]

I have a 1997 blazer lt and recently replaced the a/c compressor.After replacing ,vacuuming system ,and charging the compressor wont cycle off. It cools good but I dont want to burn up a new compressor. I know the low side pressure while on max and blower on high was around 40 I didnt check the high side before returning the gauges. Any help would be great I searched and havent found anyone with the same problem.

I just found after further investigating that it does cycle off at higher rpm's (1500 or higher) So maybe it will be ok? But I will appreciate any advice.

[MT-2500]

It will not cycle off until low side drops to around 25 lbs.

How much R-134a did you put in it?
Did you check expansion valve?
If old compressor blowed up the valve may be full of trash.
what is you vent tempt at idle and at 2K and running down the road.
We need the low and high side readings at idle and at 2K before we can tell much about it.

[nduncan]

I put 2 1/2 12oz. cans of 134 in because the under the hood label called for 1lbs. 14oz. One thing I forgot to mention was it has been from 95-100 degrees here during the day ,if that could cause this problem? I dont have access to gauges right now so I dont have that info yet. The old compressor didnt blow up, the body seals were leaking so I had to replace it ,the orfice tube screen ,and the evaporator. What is the expansion valve and where is it located?
Will I cause any damage by running it since it does cycle off while running at normal driving rpm's?

[MT-2500]

It is actualy the orfice tube.
It regulates the pressure.
What is the vent tempture on the road?
What is the low dide reading a idle and at 2K rpm?

[nduncan]

Ok I got my hands on some gauges and did a check. At idle low side is 46 lbs
high side is maxed out on the gauge
at 2000 rpm's low side is 34 lbs
high side is still pegged
It is currently 98 on the in car thermometer if it makes a difference?
This maybe a stupid ? but shouldnt both gauges be on 0 if they are not hooked up to anything because I disconnected the high side gauge and it is still reading 450 after I bled off the pressure and I cant get it to calibrate down to zero.

[MT-2500]

High side way to high and low side high is a good indication of a overcharge or you have way to much oil in the system.
Did you add oil or was the new compressor full of oil before you installed it?

I would pump it out and flush the system and replace the orfice tube and add the correct amount of oil .
Recharge with a low charge and or 2-12 oz cans 24 oz.
And see if low and high side is doing better.

The gauges with quick couplers will hold pressure on the gauge when you unplug them.
With it unplugged open all valves on gauge set and see if gauges zero.