Puzzling reading on AC gages.

In some compressors, the compressor clutch gap can actually be check and adjusted for better performance.

The increase in gap mimics a weak compressor.
This is absolutely the case on five of my cars. Specified clutch gap is 0.016” - 0.020”. Had a car where the AC would kick off after 20 minutes of operation, and wouldn’t re-engage. Clutch gap was 0.035“.

Dealer recommendation was a new compressor. $1,300 parts and labor.

I bought a $50 clutch tool, and a $5 shim kit. Disassembled the clutch with the compressor in the car, set the gap to 0.016”. Took about an hour (some parts had to be removed for access).

Works great.

Checked, then adjusted, every other similar compressor.
 
This is absolutely the case on five of my cars. Specified clutch gap is 0.016” - 0.020”. Had a car where the AC would kick off after 20 minutes of operation, and wouldn’t re-engage. Clutch gap was 0.035“.

Dealer recommendation was a new compressor. $1,300 parts and labor.

I bought a $50 clutch tool, and a $5 shim kit. Disassembled the clutch with the compressor in the car, set the gap to 0.016”. Took about an hour (some parts had to be removed for access).

Works great.

Checked, then adjusted, every other similar compressor.
I'm going to assume you don't have any leaks in these systems lol...
 
+1, and change out the receiver/drier while you're at it.
So going back in time, last fall I replaced the receiver dryer, changed a couple of seals, loaded in PAG lubricant, pulled vacuum, and loaded in the HC based refrigerant which is legal up here. R134A is hard to find on this side of the border. Over the cold winter, I lost some but not all the refrigerant. Now I’m reloading HC refrigerant, looking for leaks and evaluating the system.
 
So going back in time, last fall I replaced the receiver dryer, changed a couple of seals, loaded in PAG lubricant, pulled vacuum, and loaded in the HC based refrigerant which is legal up here. R134A is hard to find on this side of the border. Over the cold winter, I lost some but not all the refrigerant. Now I’m reloading HC refrigerant, looking for leaks and evaluating the system.
Gotcha. If the receiver dryer is a year old, the leak/leaks are a quick fix and you're not replacing the compressor [there was talk about that here] you should be OK not replacing the receiver dryer. If you're looking to go by the book and restore it to factory cold, most perfectionists would change it. If it were mine I would pull a vacuum for two hours, let it hold vacuum for two hours and charge it up after the necessary repairs. Good luck!
 
You know your orfice tubes or what ever metering device was not calibrated to use YOUR propane gas right? So you are not going to get proper cooling. Some things you need to leave to the professionals. Put the factory charged refrigerant back in.
 
If it were mine I would pull a vacuum for two hours, let it hold vacuum for two hours and charge it up after the necessary repairs.
Testing for leaks with vacuum is not the end all to testing. You need to test for leaks under pressure. Either use shop air or nitrogen. Doesn't hurt a bit to use shop air. Scanner Danner has done it for 30 plus years. Never had an issue.

You can still have a leak if tested with vacuum only guys.
 
You know your orfice tubes or what ever metering device was not calibrated to use YOUR propane gas right? So you are not going to get proper cooling. Some things you need to leave to the professionals. Put the factory charged refrigerant back in.
Thanks for the post. There are thousands of these conversions in Canada. It’s Redtek 12A.

Www.redtek.ca
 
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Testing for leaks with vacuum is not the end all to testing. You need to test for leaks under pressure. Either use shop air or nitrogen. Doesn't hurt a bit to use shop air. Scanner Danner has done it for 30 plus years. Never had an issue.

You can still have a leak if tested with vacuum only guys.
It's not, but it is a good place to start since it has to be done to charge up the system properly. I have a sniffer which works great for leak testing. The OP has a leak, we already know that.
 
Questions, in Wa state they won't let a normal Joe purchase R134 anymore. And at some point in time no one will be getting it.
So what all did you do to convert that vehicle to the newer stuff? What oil does it use?
Oh and make sure you purge All the manifold hoses before trying to add the refrigerant, else you will be adding a bunch of air that will mess the readings up too.
 
I went ahead and loaded in one more 6 oz can of Red Tech hydrocarbon refrigerant. It’s now blowing at 44F. Good enough for now. The ambient temp was 32 C which is about 90 F. The first gage shot is the static pressure. The second shot shows the operating pressures.


A5CE5E9C-2E6B-4B50-AB18-324239012D52.jpeg


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D78C6241-EA4F-4C30-8C03-1BC2B6F36C8E.jpeg
99A7B752-D086-42E2-A835-044CC9659E9D.jpeg
 
I went ahead and loaded in one more 6 oz can of Red Tech hydrocarbon refrigerant. It’s now blowing at 44F. Good enough for now. The ambient temp was 32 C which is about 90 F. The first gage shot is the static pressure. The second shot shows the operating pressures.


View attachment 166065

View attachment 166062View attachment 166063View attachment 166064
Not bad. Was the initial fill into a hard vacuum?

The only concern with blends is that they fractionate when they leak, so full release and refill is prudent. Install as a liquid is important too.
 
After pulling the vacuum, I closed the valve to the low side. Since at the time I did not have a loading valve for the yellow hose, I closed the valve at the low side port, removed the blue hose, connected a loading hose with a can attached and opened the valve, so, yes it would have been a full vacuum then the first can went in. Here is my loading hose when I put in the last can of refrigerant. This is Red Tek 12A hydrocarbon refrigerant.

1DEF7CF7-6754-4BEC-ABF3-CF2C5EAE7598.jpeg
 
A good accessory is a valve with a threaded connection for a can in top to load refrigerant in through the yellow hose. I did a rookie mistake and accidentally purchased one that was made for self sealing refrigerant cans. My cans were the type that required piercing, so I’ll probably purchase one off Amazon.
 
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