300TE 4MATIC (124.290) L6-3.0L (103.985) (1991)
1.
If A/C system is void of any R12 refrigerant or the compressor will not engage, check refrigerant compressor for binding by rotating A/C
compressor by hand.
2.
If A/C compressor binding is not present, fill A/C system with fresh/recycled refrigerant and perform refrigerant leak test. (Figure 1).
CAUTION!:
Observe specifications on Fill Capacity Label.
3.
Check for proper operation of A/C system.
Models 124, 129
If parts require replacement, only R134a-type components are to be installed.
Models 107,116, 123, 126, 201
If the A/C lines, condenser or evaporator require replacement, please continue with "C. Removal of Mineral Oil from A/C System".
Note:
If replacing the A/C compressor, use a compressor designed for refrigerant R134 if available. If a R134a compressor is not available as a spare part,
be certain to drain the mineral oil from the new R12 compressor prior to installation.
CAUTION!
In this case, do not refill A/C system with R12, please continue with "D. Replacing Receiver/Drier".
C. Removal of Mineral Oil From A/C System
Note:
During the conversion to R134a refrigerant, it is important to remove as much mineral oil from the A/C system as possible.
Procedure
1.
Press button.
2.
Set temperature selector wheels to max. heat detent (red zone).
3.
Press button.
4.
Engage max. A/C fan speed (Tempmatic) or Press button if automatic A/C.
5.
Close all doors and windows.
6.
Run engine at 2000 rpm for approx. 10 minutes.