Conversion of A/C System 1991-1992

EQUIPMENT AND MATERIALS FOR RETROFITTING A/C SYSTEMS FROM R12 TO R134a REFRIGERANT 1991-1992


EQUIPMENT REQUIRED:

- Recovery/filling station for R12
- Recovery/filling station for R134a
- Leakage detector R12/R134a

MATERIAL:




Retrofit kit P/N 9145666-5 (see illustration)
Thread locking fluid P/N 1161351-0, (or commercially available).


CONVERSION OF A/C SYSTEM FROM R12 TO R134A "RETROFIT" 1991-1992

B4

LOCATION OF ORIFICE




The orifice is located in the high pressure pipe at the right sidemember under the generator. To get access to the orifice, the car must be put on a lift and the engine splash pan must be removed.

B5

REMOVE ORIFICE

- Clean connection and surrounding body area thoroughly

- Undo nut on connection




- Pull or work out the orifice (it is not threaded.)

- Take care not to break it and ensure that the entire unit is removed.

- Remove joint O-ring.

B6

INSPECT ORIFICE FILTER:




Is the filter heavily clogged or heavily contaminated with metal particles? If so, the compressor may be in poor condition and should be replaced.

As a rule or thumb: If more than 3 of the 5 orifice filter sections are clogged (Fig. B) condition of the compressor oil should be inspected. If compressor oil is black, heavy contaminated or if compressor is dry, the compressor should be replaced Picture A is normal.

The orifice should not be reused once it has been inspected. There is a new orifice in the conversion kit.

B7

IF THE COMPRESSOR NEEDS REPLACING:




A new compressor is filled with mineral oil Drain this oil and replace it with the all ester oil (200 ml 6.8 fl oz) from the conversion kit Save residual oil in can to lubricate O-rings

To replace the compressor see Service Manual. Section 6 (82-88) TP31120/1

B8

INSTALL NEW ORIFICE




If new orifice has a black O-ring installed discard the black O-ring Install new yellow. lubricated (use ester oil) O-ring (inner dia 6.7 mml 7/64") on the new orifice

- Install a yellow lubricated O-ring (inner dia 108 mm 27/64") in the pipe joint at the firewall or side member

- Install orifice and connect pipes

- Tighten the nut on the joint to 25 Nm (19 ft lbs)

B9

PREPARE NEW ACCUMULATOR




Fill accumulator with ester oil (200 ml 6.8 fl oz) on the inlet side

Replug accumulator

NOTE!
If compressor was replaced in previous step no ester oil is needed for the accumulator.

Save residual oil in can to lubricate O-rings

B10

REMOVE ACCUMULATOR

Undo.




- pipe connectors at the accumulator inlet, outlet and at thick/thin pipe joint between the accumulator and evaporator

- pressure switch connector and remove the pressure switch

- remove existing O-rings. Note which size goes where.

- accumulator.

Transfer foam padding to new accumulator.

If system is left open, cap/plug open pipes to avoid moisture in the system.

B11

INSTALL NEW ACCUMULATOR




- Install accumulator, but do not tighten.

- Install new yellow O-rings inner dia. 17.2 mm (11/16") (lubricated with ester oil residue in can) onto pipes, if not already done.

- Install new service valve pipe on accumulator inlet and evaporator pipe. Hand tighten.

- Tighten accumulator clamp.

- Connect the accumulator outlet pipe. Hand tighten.

- Tighten pipe connections (inlet and outlet) to 45 Nm (33 ft. lbs).

- Tighten pipe-joint to to 33 Nm (24 ft. lbs).

- Using new O-ring, inner dia. 8.9 mm (11/32") (lubricated with ester oil), fit the pressure switch onto the accumulator. Tighten to 3.5 Nm (30 in. lbs).

- Connect the pressure switch connector.

B12

CHECK THE A/C SYSTEM

Evacuate A/C system




- Connect R134a recovery/recycling station Evacuate system for at least 50 min

- Check that the system can hold a vacuum. The vacuum must not sink within 4 minutes.


FINALIZING WORK

B13

INSTALL LABELS

While evacuating, the following can be carried out:




- Complete the light blue rectangular R134a "RETROFIT" label before removing carbon paper.

Using ball-point pen, note:

- technician initials,
- dealer number, if applicable, (or repair shop name, city state).
- date.

- Clean the old R12 label on the bodywork, remove carbon paper and stick the new, light blue rectangular R134a "RETROFIT" label over it. The old label should be completely covered.

- Using mineral spirits, clean top of accumulator, then stick the round R134a "RETROFIT" label onto it.

B14

PLUG OLD SERVICE VALVES







- Cap service valves which will not be used, two on the compressor (in some cases there are no valves) and one on the accumulator.

- Use caps provided in conversion kit.
- Use thread locking fluid, P/N 1161351-0 or equivalent.


B15

FILL WITH REFRIGERANT R134A




When evacuation is complete, fill with 200 grams (7 oz = 0.44 lbs.) of refrigerant R134a. Test for leaks with a leak detector. Repair any leaks.

When no leaks are found, top up to total capacity amount of refrigerant R134a specified on the enclosed label.

240 1991-1992 1000 grams (2.2 lbs.)

B16

CARRY OUT A FUNCTION TEST

- Start engine.

- Start A/C

- Check that the compressor starts and runs normally without making any unusual noises. If compressor does not operate normally, fault trace according to normal procedure.

- Check that air from dashboard vents is cool.

- If not, check that heater valve closes fully.

- Switch off the engine.




- Re-test for leaks using leak detector. Repair any leaks found.

END OF RETROFIT PROCEDURE FOR M.Y. 1991-1992