VALVE GP-RELIEF 1211559 - Caterpillar

Complete Check of Refrigerant Compressor Oil
When the replacement of a component is necessary, follow the procedures below. The procedure determines the amount of refrigerant oil (lost oil) that is needed in the refrigerant compressor.
Operate the engine at 1000 rpm. Set the temperature on maximum cooling setting. Set the fan speed to HIGH. The system will stabilize in a minimum of 10 minutes.
Stop the engine. Remove the refrigerant charge from the system. Install a plug in all open lines. Refer to Testing and Adjusting, "Refrigerant Recovery" for the proper procedure.
Remove the refrigerant compressor from the machine. Put protective caps on all fittings and hoses.
Illustration 1 g02559238
(1) Plug (refrigerant oil change)
(2) Electrical harness
(3) Pulley
(4) Hose (high pressure)
(5) Hose (low pressure)
(6) Serpentine belt
Place the refrigerant compressor in a horizontal position so that refrigerant oil change plug (1) is down. Remove refrigerant oil change plug (1) from the refrigerant compressor. Drain the refrigerant oil into a clean container. Rock the refrigerant compressor back and forth in order to remove all the refrigerant oil. Also, rotate the refrigerant compressor shaft in order to drain the rest of the refrigerant oil that is in the oil sump. Record the volume of drained refrigerant oil. Inspect the refrigerant oil for the following items:
Contaminants
Metal chips
Rubber particles
Foreign materialDispose of the refrigerant oil in a suitable container. Use the following list as a guide for adding refrigerant oil into the refrigerant compressor:
If the amount of refrigerant oil that is drained from the refrigerant compressor is 177 mL (6 fl oz) to 240 mL (8 fl oz), put the same amount of new refrigerant oil in the refrigerant compressor. Never refill with more than 240 mL (8.1 fl oz) of oil to the refrigerant compressor unless the system has been flushed.
If the amount of refrigerant oil that is drained from the compressor is less than 177 mL (6 fl oz), add 177 mL (6 fl oz) to 240 mL (8.1 fl oz) of new refrigerant oil to the compressor.
If a new refrigerant compressor or a rebuilt refrigerant compressor is installed, drain all of the refrigerant oil from the refrigerant compressor and add 177 mL (6 fl oz) to 240 mL (8.1 fl oz) of new refrigerant oil in the refrigerant compressor.
If the system was flushed, do not remove the refrigerant oil from a new refrigerant compressor.
Refer to Table 1 if individual components are replaced without charging the refrigerant compressor or without flushing the system.
Table 1
Refrigerant Oil Capacities for Component Replacements
Compressor 240 mL (8.1 fl oz)
Condenser 30 mL (1 fl oz)
Evaporator 90 mL (3 fl oz)
Receiver-Dryer 30 mL (1 fl oz) If too much oil has been added to the system and a total of more than 325 mL (11 fl oz) of oil is in the system, the cooling capacity of the system will be reduced. If too little oil has been added to the system, the compressor may fail due to a lack of lubrication.If the failure of a component, causes particles of metal or