R-134A Systems
When servicing R-134a air conditioning systems always use the R-134a manifold gauges, gas leak detector assembly, tool No. 07116-38360, or equivalent, and vacuum pump adapter. Use R-134a manifold gauges to prevent R12 and R12 compressor oil contaminating the R-134a system. The R12 leak detector is not sufficiently sensitive, always use the R-134a gas leak detector assembly tool. By adapting a vacuum pump adapter, the vacuum pump can be used for both R-134a and R-12 air conditioning systems. The vacuum pump adapter has an internal magnetic valve. When evacuation is completed and the vacuum pump switch is turned off, the magnetic valve opens allowing atmospheric air into the manifold gauges to prevent the back flow of oil from the vacuum pump into the gauge hose. Be sure to turn off manifold gauge immediately after evacuating system. Ifnot, the line will temporarily open to atmosphere.
System Empty
Do not pressure test the R-134a system with compressed air. Some mixtures of R-134a refrigerant have been shown be to combustible at higher pressures. Use gas leak detector assembly, tool No. 07116-38360, or equivalent, designed for R-134a systems.
1. Evacuate A/C system.
2. Prepare 10 oz. R-134a refrigerant charge to be injected into system. Refer to "Charging System" for procedure.
3. With engine Off, use the gas leak detector assembly, tool No. 07116-38360, or equivalent, designed for R-134a system and inspect for leaks. Fittings, lines or components that appear to be oily may indicate a refrigerant leak. To inspect the evaporator core for leaks, it is possible to insert the leak detector probe into the recirculating air door opening. With the blower at low speed and the selector in FLOOR and RECIRC mode check for leaks at left and right heater outlets. If no leak is present, fill system as outlined under Performance Test.
Low Level
1. Start engine with A/C On for five minutes to allow system to reach operating temperature and pressure.
2. With engine Off, use the gas leak detector assembly, tool No. 07116-38360, or equivalent, designed for R-134a system and inspect for leaks. Fittings, lines or components that appear to be oily may indicate a refrigerant leak. To inspect the evaporator core for leaks, it is possible to insert the leak detector probe into the recirculating air door opening. With the blower at low speed and the selector in FLOOR and RECIRC mode check for leaks at left and right heater outlets. If no leak is present, fill system as outlined under Performance Test.