My A/C was not blowing cold and my compressor clutch was not engaging. With Forum suggestions, I put a 20 oz. can of A/C pro on the low side and the clutch started engaging and A/C blowing colder. When the clutch cycles off the pro gauge goes into the low (white) zone. When the clutch engages it goes about 3/4 into the green zone and then drops back to the white zone when it disengages. At idle the clutch does frequently cycle and the rad fan is running normal.
One question is, should the clutch frequently cycle while in idle and I am running the A/C? I talked to the A/C Pro people and they were not much help with questions because they are not that familiar with these older type of cycling compressors but seemed to think the drop to the white zone when clutch disengages is normal. Also when the compressor engages the needle goes about 3/4 into the green as I mentioned. That makes me believe I could add more refrigerant to get the needle to go more into the green zone but I don't know and the A/C pro folks don't either.
I am happy to try and better explain this if needed. Basically, should I try to add more refrigerant to get the green higher or leave it alone and does it sound like my A/C is operating normal? Thanks Sandy

 

Honestly, get a manifold and gauge set, so you can see what the high side is doing. Harbor Freight has a servicable set that won't break the bank

 

Surely not opposed to that if I actually need it. But I don't need it if the system is operating properly. Let me see if anyone chimes in. Sandy

 

Without gauges you can't judge the high side pressure. From what you describe it is probably a blocked orifice tube.

 

It sure could be. We did install a new orifice tube when we put the NEW compressor in about May of 2018. As I recall there is a blue and a red or yellow tube. If I do need one, do you know the color I need? What would the high side show on the gauge if it was the orifice or another problem? I have never owned a manifold gauge set. Thank you. Sandy

 

Right now on normal or max A/C the clutch will engage about every three seconds and go off for about three seconds then back on for three. It is constant. This doesn't seem right but not sure.

 

I can't help you any, but, are you using the gauge that came with the can of Freon? If so, most of those gauges aren't any good . The last can of Freon I bought several months ago must have had a good gauge. It didn't rock everywhere like the cans (with a gauge) I've bought in the past. I have a leak in my air conditioner somewhere and going to have to pay a pro the fix it this summer

 

Thats excessive, even for an older A/C system.

 

Thank you. I will be getting a gauge set so as others have said,I need to see the high side. Thanks for all the help from everyone. I'll keep you posted. Sandy

 

As was suggested in your other a/c thread, you need to put real gauges on it to monitor both high and low pressures with real numbers and not a zone. It sounds like you are still low on refrigerant but you can not just keep adding more.

Another problem is that you put 20oz in system which is a lot. I’d think it would be fairly obvious to see where that went. Around the seals or the condenser should have an oil mark from the leak. Have you used the light to check for dye stains?

 

is the system converted to R134A or still R-12?
if converted was it flushed and new pag oil added? there are way to many unknowns for a proper diagnosis.

 

It was converted by the only PO. My brother in laws mechanic installed a new compressor May of 2018. We added Pag oil and dye and a new orrifice. We did not install a new drier. Black light does not show leaking.
As I recall the system cycled after the install like now and we had to add more freon to make it stop. I will have a gauge set this afternoon and will use it in the morning. I will post my results.

 

I have the gauge. What should the high and low pressure be? Thank you

 

It depends on air temperature.

 

Temp outside is 64*