Conversion of A/C System 1975-1990
CONVERSION OF A/C SYSTEM FROM R12 TO R134a "RETROFIT" 1975-1990A4
Turn off radio, then;
REMOVE:
- battery negative lead
- glove compartment
- the panel under the glove compartment
- side panel to the heater
- right defroster outlet
- air duct.
A5
REMOVE THERMOSTAT FROM EVAPORATOR COVER
(Applies only to 240 cars, model years 1975-1978).
NOTE!
The location of the thermostat (1) can vary. The capillary pipe on later model years (1979-) is located on the evaporator pipe.
A6
Remove:
- insulation sealant.
- the cover (2).
A7
REMOVE THE OLD EVAPORATOR
NOTE!
Plug all open pipe ends and connections to prevent moisture from entering the system.
Remove the screwed joints from the evaporator.
Carefully pull the evaporator out.
NOTE!
Do not forget to remove the thermostat sensor body which is located on the evaporator's outlet pipe (the thick pipe).
INSTALLATION:
NOTE!
Clean the old sealant from the inside of the housing. Inserting the new evaporator may be difficult if this is not done.
NOTE!
Remove the backing paper from the butyl tape on the rear of the new evaporator.
A8
INSTALL THE NEW EVAPORATOR
NOTE!
Use both thumbs to press down. Make sure the evaporator goes all the way into the housing.
A9
Install the new expansion valve.
NOTE!
To avoid the capillary pipes from breaking when they are bent, perform this procedure carefully.
A10
CONNECT THE REFRIGERANT HOSES
Use new seals for O-rings. Lubricate with ester oil. Tighten to 30 Nm (22 ft. lbs).
A11
INSULATE THE EVAPORATOR PIPES AND SCREWED JOINTS. INSTALL THE COVER
NOTE!
Do not insulate the expansion valve.
A12
INSTALL:
- defroster outlet
- air duct
- glove compartment
- the panels
The method for replacement of the compressor is described in service manual Section 8 (82-88) TP 31120/1
A13
Drain mineral oil from the compressor and replace with ester oil. Use the 0.125 liter (4.23 fl. oz) can of ester oil from the kit.
NOTE!
On York and Delco compressors an additional 0.125 liters (4.23 fl oz) is required.
A14
If the compressor must be replaced: Drain oil. New compressors are always filled with mineral oil.
After replacing the compressor Fill with 0.125 liters (4.23 fl oz) ester oil P/N 1394828-6.
A15
If the compressor is not to be replaced:
ON LATER MODEL YEARS WITH DIESEL KIKI/ZEXEL COMPRESSOR:
Remove plug at the rear of the compressor. Drain oil. Replace oil with 0.125 liters (4.23 fl. oz) ester oil. Fill oil through the plug in the upper section of the compressor. Use the syringe.
ON EARLY MODELS WITH YORK COMPRESSOR:
Remove plug in the side of the compressor Use the syringe to suck out the oil. Make sure the hose goes all the way down. If necessary turn the compressor crankshaft slightly.
Fill with 2 x 0.125 liters (2 x 4.23 fl. oz) ester oil. Use the syringe.
ON 260 MODELS WITH B27/B28 ENGINES AND DELCO COMPRESSOR:
Release the compressor from its mounting. Lower the compressor.
NOTE!
The hoses can remain in place. Empty mineral oil through the plug in the bottom. Fill with ester oil (2 x 0.125 liters, 2 x 4.23 fl. oz) using the same plug as for draining. Use the syringe.
NOTE!
On 240 diesel cars up to model year 1989 with Sanden 508 or 510 compressors the compressor shaft seal must be replaced, see page 19. After replacing the seal continue to operation A16.
REPLACEMENT OF THE DRIER
A18
Install the new drier in the car.
Remove factory fill and move A/C hose up to fitting on the new driver.
Use new O-rings. Lubricate the O-rings with a few drops of ester oil remaining in the can.
CONNECT:
- hoses from the condenser to the "in" connection on the drier
- the new filling valve between connections out" on the drier and the hose to the evaporator.
Tighten connections to 25 Nm (18 ft. lbs). Connect the connector to the pressure sensor.
A17
REPLACE HOSE BETWEEN COMPRESSOR AND CONDENSER
Use new O-rings. Lubricate rings with ester oil. Tighten connections:
To condenser to 17 Nm (12 ft. lbs). To compressor to 30 Nm (22 ft. lbs).
NOTE!
On cars with B27/828 engines. DO NOT REPLACE HOSE.
CHECK THE A/C SYSTEM
A18
Vacuum pump the A/C system
Connect R134a recycling/filling unit. Start vacuum pumping and run for at least 45 minutes.
Check that system keeps a vacuum. The vacuum must not sink more than one line on the scale during a 4 minute period.
Refer to Service Manual Section 8 (82-88) TP 31120/1
FINALIZING WORK
A19
The following work can be completed during the time required for the vacuum pumping:
Apply the new round R134a "RETROFIT" label next to the receiver
Fill in the oblong label before the backing paper is removed. Clean off the old R12 label on the chassis.
Apply the completed new light-blue R134a "RETROFIT" label over the R12 label. Make sure the old label is completely covered.
A20
Install blocking plugs on the service valves on the compressor which will not be used any more.
Use locking fluid P/N 1161075-5.
A21
REFILLING SYSTEM WITH REFRIGERANT
On completion of vacuum pumping, fill system with 200 gr. (7 oz) of R134a refrigerant.
For instructions on use of the units refer to SB 87-213 and 87-218.
Check for leakage detection with a leak detector afier filling. Correct any leakage.
When no leakage is detected fill with remainder of refrigerant R134a to the amount stated on the label, (1000 grams, 35.3 oz.).
A22
VERIFY A/C FUNCTIONS
Start engine and turn on the A/C system. Check that the compressor starts and operates normally without noise.
Check that air in the car is cooled. Refer to Service Manual TP 31120/1, Section 8 (82-88), performance test, page 178-179. If the performance of the system is not to the stated levels, check that the hot water valve is closing completely.
Turn engine off.
Check for leakage detection with a leak detector. Repair any leaks.
END OF RETROFIT PROCEDURE FOR M/Y 1975-1990.