Greetings
I am looking for information on materials and procedures. I will be working on two '95 Grand AM's. One seems to be working ok but after measuring the high and low sides with a pressure gage it shows that it is low on refrigerant. The other had the condenser removed because of collision damage. I plugged the ends with ear plugs right away but there is evidence that it had been worked on before.
First, there several different kinds of refrigerant available. Some is just straight 134, some has dye in it. some has stop leak in it and some has oil in it. The last one that I looked at was made by EF Products It says Quest at the top of the can. It says that it contains synthetic "A/C booster" plus "Stop Leak". It claims to make air colder. It says that it adds lubricant also.
Any recommendations on what type to use?
When Filling the car that is working, should I put the gage on the high pressure side and add refrigerant until the gage is in the pressure range for the ambient temperature? Is there anything else that I should do?
On the car that had the condenser removed, I will apply a vacuum to the low pressure side for several hours then fill. (One thing that I don't understand is how a vacuum on a pressure system will accurately check for leaks. Wouldn't the vacuum pull openings together and pressure open them up again?) I am thinking about taking a chance that the dryer is ok. If I am wrong what will happen? How do I know if there is enough oil in the system? The factory manual says to use a 525 viscosity oil but the store sells it in low, medium and high viscosity.
Thanks Scott