Conversion of A/C System - Retrofit

CONVERSION OF A/C SYSTEM FROM R12 TO R134a "RETROFIT"

The method described below is for installing Basic kit P/N 91456608. This is in principle, the basic method for installing Basic P/N 91456616 or Supplementary kits according to pages 8-10.

EMPTY REFRIGERANT FROM SYSTEM

Refer to pages 243 and 246 in Service Manual Section 8 (82-88) Body Fittings. Interior, Climate Units 740, 760 1982-19..

A1
Remove:
- battery negative cable terminal
- Receiver.

A2



Use rust inhibitor P/N 1161422-9 on all screw joints which are to be detached

Allow the inhibitor several minutes to work before undoing screwed joints.
Never use excessive force

NOTE!
Under no circumstances use heat when removing.

A3
DETACH:




- ETF/KRU valve at bracket. Remove circlip and valve (where installed)
- pipe connections at the receiver inlet and outlet (refer to remarks below)
- the pressostat connector. Remove pressostat; this will be reused
- existing 0 rings (note sizes). Replace with new rings from kit.

A4
Remove screws holding the Receiver clamp

A5
Lift out Receiver

REMARK:

On older cars or cars where the A/C system was installed as an accessory, there is no ETF/KRU valve.




In this case remove the pipe (see arrow) at the firewall. Then use Supplementary kit (1) P/N 9134032.3 for installation.

A8



Plug all open pipe ends to prevent moisture from entering the system.

A7
Wipe clean around all connections that have been opened.

A8
EXPANSION PIPE (ORIFICE) LOCATION:




On model years 1991 and earlier (780 -1990) the orifice is located in the receiver inlet at the firewall (see arrow).

Note!
Make a point of noting how the orifice is sited in the pipe. Refer to this and the next illustration.

A9



On model year 1992 and later (780 1991-) the orifice is sited in the High-Pressure pipe at the pipe joint on the side member, arrow A.

Note!
In some cases the work will be made easier if the pipe for the evaporator inlet is removed at the firewall (the right side pipe as shown at Arrow B). The 0 ring must then be replaced, P/N 3537503-9.

A10
REMOVE EXPANSION PIPE (ORIFICE)

Clean the joint thoroughly.

Remove the union nut.




Pull or "wiggle" the expansion pipe out (it is not threaded). Take care not to break off the expansion pipe. Make sure the whole unit is removed

A11
INSPECT EXPANSION PIPES (OPENING'S) FILTER SECTION




If the filter is choked or there are a lot of metal particles in it (refer to illustration) then the compressor may be in poor condition and need replacing with a new unit.

A rule of thumb: If more than 3 of the 5 filter sections are clogged (Fig. B) then the compressor oil should be examined. If the compressor oil is black and heavily contaminated, or if the compressor is dry, then replace the compressor with a new unit. Fig. A shows an orifice that is normal.

After inspection the old orifice should be scrapped. The conversion kit contains a new one.

A12
IF THE COMPRESSOR MUST BE REPLACED:




The new compressor unit as a replacement part is filled
with mineral oil. Empty the oil and replace with ester oil

(200 ml, 6.76 fl. oz) from the conversion kit.

Warning!
Do not fill the Receiver with oil if replacing the compressor.
Only fill the compressor using the filler plug not
through the inlet or outlet connections.

Note!
The 0 rings on the compressor inlet and outlet must always be replaced with new ones.

These 0-rings are not included in the kits and must be ordered separately.

For compressor replacement refer to the Service Manual Section 8 (82-88) Body Fittings, Interior, Climate Units 740, 760 1982-19..

A13
INSTALL EXPANSION PIPE (ORIFICE).

Install a new yellow lubricated 0 ring on the new expansion pipe. Compare size of the new 0 ring with the old one so they are the correct dimension.

Install a lubricated 0 ring in the pipe joint at the firewall (or side member).




Install expansion pipe (orifice).

Tighten the joint nut to the evaporator (or at the side member) to 12 Nm (g ft. lbs.).

A14
TOP UP OIL LEVEL IN NEW RECEIVER




Fill the receiver through the inlet side with ester oil supplied in the conversion kit.

Note!
If the compressor has been replaced and filled with ester oil in previous steps, no additional ester oil is needed in the receiver.

REMARKS: On older cars without pipes for ETF/KRU valve:




Install pipes from Supplementary kit (1) P/N 9134032-3. Finger tighten against the receiver. Use new lubricated 0-rings. Connect filling pipe (U pipe) using a new lubricated 0-ring.

A15
Install following:




- Receiver in the car

- new lubricated 0 rings at the joint between the evaporator and at the receiver outlet.

- pipe to evaporator and at the receiver outlet. Tighten by hand.

A18
Tightening and torques:

- the pipe between the evaporator and receiver: 27 Nm (20 ft. lbs) at evaporator and 45 Nm (33 ft lbs.) at the Receiver

- the pipe at the receiver outlet with 45 Nm (33 ft. lbs)

- filler pipe (U pipe) with 16 Nm (12 ft lbs)

- screws on the receiver clamp.

A17
Use a new 0 ring for the old pressostat, (lubricate with ester oil) and install it on the receiver

Compare size of the new 0 ring with the old one to ensure correct dimension. Tighten the pressostat with 3.5 Nm (31 in. lbs).

A18
Connect the connector to the pressostat

A19



Install the new SAE filler valve for R134a

ALTERNATIVE 1: Use a new yellow lubricated 0 ring and install on the filler pipe (U pipe). Install SAE filler valve. Tighten with 16 Nm (12 ft. lbs).

ALTERNATIVE 2: Use a new yellow lubricated 0 ring. Install on the filler pipe (U pipe). Install SAE filler valve and circlip (included in basic kit P/N 9145660-8). Tighten SAE filler valve with 16 Nm (12 ft. lbs).

INSPECT A/C SYSTEM

A20



Vacuum pump the A/C system Connect R134a recycling/filling unit
Start vacuum pumping and continue for at least 50 min

Check that system keeps a vacuum. The vacuum must not sink during a 4 minute period.

FINALIZING WORK

A21
While evacuating, the following work can be carried out:




Complete the light blue rectangular R134a "RETROFIT" label before the protective paper and carbon is removed.

Using ball-point pen, note:

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

Carefully clean off the old R12 decal on the bodywork, remove carbon paper and stick the new, light-blue R134a "RETROFIT" label over it. Make sure the old label is completely covered.

Using mineral spirits, clean top of accumulator; then stick the round R134a "RETROFIT" decal on the receiver.

A22






INSTALL THE CAPS (INCLUDED IN KIT) ON THE SERVICE VALVES WHICH ARE NO LONGER USED.

Two on the compressor (in certain cases there are none on the compressor) and one on the receiver (see illustration below).

Use locking fluid P/N 11613510 or equivalent on the caps.

A23
REFILLING SYSTEM WITH REFRIGERANT




On completion of vacuum pumping, fill system with max. 200 grams (0.44 lbs) refrigerant R134a.

Leakage testing after filling. Use leakage detector. Repair any leaks. (Refer to Service Manual Section 8 (82-88) Body Fittings, Interior, Climate Units 740. 760 1982.19..

When no leakage is detected fill with remainder of refrigerant R134a to the amount stated below:

740 - 1990 - 1100 grams - 2.4 lbs
760 - 1987 - 1100 grams - 2.4 lbs
780 - 1991 - 1100 grams - 2.4 lbs

740/940 - 1991-1992 - 950 grams - 2.1 lbs
940SE/760/960 - 1988-1992 - 900 grams - 2.0 lbs

VERIFY FUNCTIONS

A24
Start:

- engine
- A/C system.

A25
CHECK THAT:

- compressor starts and operates normally without unusual noise

- in-car air is cooled. See performance testing, Service Manual Section 8 (8288) Body Fittings. Interior, Climate Units 740, 760 1982-19..

A28
STOP ENGINE




Check leakage with leakage detector. Repair any leaks indicated.

Fault tracing, refer to Service Manual Section 8 (8288) Body Fittings, Interior, Climate Units 740, 760 1982-19..