Checking/Adding Refrigerant Oil

TM 10-3930-673-34

(13)

Perform task f.).

f. Checking/Adding Refrigerant Oil.

NOTE

It is not necessary to check or add

oil as routine maintenance. It is

necessary to check oil when the

evaporator, condenser,

compressor, or receiver/dryer has

been replaced, or there was an

obvious oil leak. When a system

is discharged, it is also necessary

to replace any oil carried out with

the refrigerant.

Vehicle must be on level ground.

(1)

Charge A/C system (refer to task e.).

(2)

Make sure low pressure gage valve (1)

and high pressure gage valve (2) on

manifold gage set (3) are turned

clockwise to off position.

(3)

Start engine and turn on A/C system

(refer to TM 10-3930-673-10). Allow

engine to idle for approximately 10 to

15 minutes. Stop engine.

NOTE

Do not allow refrigerant R-134 to

escape too quickly. Refrigerant oil

will escape.

When high pressure gage and low

pressure gage read "zero", the

compressor is discharged.

(4)

Turn low pressure gage valve (1) and

high pressure gage valve (2)

counterclockwise slightly to permit refrigerant in the compressor (5) to slowly escape

through center hose (4) until gages read "zero".

(5)

Close low pressure gage valve (1) and high pressure gage valve (2).

(6)

Remove fill plug dipstick (6) from compressor (5) and wipe clean.

(7)

Insert the dipstick to its stop position.

(8)

Remove dipstick from compressor (5) and count number of increments oil level is up to

on dipstick.

15-11