The amount could very some depending on the year make, model and engine size. You can get the correct amount on the website in the link below. You will find it under the "Find your cars low side port" icon. Just follow the steps with your exact car information and click on the A/C Refrigeration and Lube Specifications
Your 1990 has R12 refrigerant in it which isn't available anymore at parts stores. To add refrigerant to your vehicle you will have to get the a/c system vaccuumed and retrofitted to accept new r134a refrigerant and pag100 compressor oil. You can take it to a shop to get it vaccuumed and retrofit it yourself with kits from your local Autozone. -broncomudder89
Its always best to drain the oil from the old compressor and then add that same amount back to the new compressor but to be on the safe side add 4 ounces and prime it on the bench first...
No, if you mix them they will form a gel and ruin the compressor. You will have to have the system evacuated and replaced with the new refrigerant.
The compressor will "cycle" on and off if the refrigerant level is getting low. There is a sensor that detects the pressure of the refrigerant on the "low" side. If there is enough pressure, the compressor can turn on. When the compressor pulls some of the refrigerant and compresses it to the "high" side, there will be less refrigerant for the low side, which causes the sensor to turn the compressor off again, then the refrigerant migrates back to the low side and the compressor can cycle back on. Once the refrigerant level gets so low that the sensor won't allow it to turn on, you're done. You need to find the leak, repair it and recharge the system. Most AC systems that leak that fast have a worn seal and/or main shaft bearing in the compressor. You can't really repair a compressor so if that's your problem, just plan on getting a new one. Look at the compressor, around the pulley. If you see oil, that's your leak.
When you are replacing a compressor. Chances are that the compressor's internal motor had a burnout when this happens the there is a chemical reaction that makes everything very acidic this in-turn contaminates the refrigerant as well. The old refrigerant would be reclaimed and sent to a a reclamation center where it would be incinerated under the guidelines by the Dept of EPA .
If you are only changing the compressor, add 3 ounces into the suction port of the compressor before you attach hoses. After hoses are attached rotate the compressor by hand clockwise several turns to distribute the oil.
There is no fuse for the compressor itself, if the compressor is not working, the low pressure switch has activated and there is not enough refrigerant in the system. Have your AC system serviced by a good shop or your local Chrysler dealer.
Diesel Engine...Discharge the refrigerant system using a certified recycling/recovery station.Disconnect the 2 refrigerant lines from the compressor. Cap the openings immediately!Loosen the pivot and adjusting bolts. Remove the belt.Disconnect the clutch wire at the connector.Remove the 5 bolts attaching the compressor to the mounting bracket.Remove the compressor.Installation is the reverse of removal. Use new O-rings coated with clean refrigerant oil at all fittings. If a new, replacement compressor is being installed, remove the shipping plates and add 120ml (4 fl. oz.) of clean refrigerant oil through the service ports. Assemble all parts loosely and adjust the belt tension. Tighten all mounting bolts to 32 ft. lbs. (43 Nm). Tighten the compressor manifold bolts to 13-17 ft. lbs. (18-23 Nm). Evacuate, charge and leak test the system......
Legally you can't without the EPA's Secton 609 certifacation, because any refrigerant in the system must be removed by a licensed technician. And even if its empty of refrigerant, after you relace the compressor you must pull a vacuum on the system to remove air and moisture. I would recomend taking it to a garage. The guy above probably owns an AC garage. You need to have a certified mechanic "discharge" and "re-charge" the refrigerant. However, the act of replacing the AC compressor can be done by you (although this depends on "you"). My local shop charges $85 to remove the refrigerant and replace it again after I have changed out the compressor. Tomorrow I will take the old compressor off and put the new one in...from what I gather so far...this entails removing the plastic cover below the compressor, remove the belt, remove the compressor, replace the new one and use a wrench on the belt "auto-tensioner" to get the belt back on. Run the car and make sure it works properly...then take it back to the garage, get the refrigerant re-charged and you should be good to go!
This is not a DIY job. It is illegal to release refrigerant into the atmosphere. Special equipment must be used to purge the system before removing and re-installing the compressor. The new compressor and system must then be charged correctly with refrigerant and oil. Take it to a professional.
New AC compressor for my 93 Ranger was $156.
A full day service call plus the cost of the compressor, refrigerant and new driers.Plus perhaps disposal charges of the old one since it contains oil. Depending on the age and condition of your system sometimes it makes sense to replace the entire unit.