A/C Compressor Shaft Seal - Replacement
Group: 87Number: 91-05
Date: April 30, 1991
Subject:
A/C Compressor Shaft Seal, replacing
Model(s):
Passat, Corrado from 1990 m.y.
Golf, GTI, Jetta, GLI (GTX in Canada) from 1985 m.y.
Vanagon, Cabriolet from 1984 m.y.
Condition
General Information
A/C performance is poor. Diagnosis of refrigerant system with leak detector reveals refrigerant leak at front seal of compressor shaft.
A/C system leak test with electronic refrigerant leak detector.
Labor Operation Number: 87 01 71 0
Suggested repair time: 40 TU
Service
WARNING
Follow all recommended safety precautions listed in the Repair Manual Microfiche to avoid injury.
WARNING
Automotive refrigerants containing CFC's are hazardous to the earth's atmosphere. To protect our environment, use an Underwriter's Laboratory (UL) approved refrigerant recovery/recycling unit such as Kent-Moore ACR 3, or equivalent, whenever discharging an A/C system.
WARNING
The A/C system should only be serviced by trained personnel familiar with:
^ equipment use
^ related safety procedures
^ regulations governing the discharging handling and disposal of automotive refrigerants.
Caution
Always follow manufacturer's instructions when using a refrigerant recovery/recycling unit.
^ Discharge A/C refrigerant system, use refrigerant recovery/recycling unit
Note:
If the vehicle is received with no refrigerant in the A/C system, the receiver drier must be replaced.
^ Remove A/C lines from compressor.
^ Plug A/C lines with suitable plugs to prevent contaminating of receiver drier with moisture.
^ Remove compressor from vehicle.
Notes:
Refer to Repair Group 87 of the Repair Manual Microfiche for removal and installation procedures.
All compressor front bearing seal repairs must be performed on a clean dry service bench.
When servicing A/C compressors, verify the model number of the compressor, i.e. SD-5O8 or SD-7O9, to insure correct replacement parts are ordered. Many older Vanagons may have been upgraded to the seven cylinder compressor (SD-709). VIN information on the parts microfiche will not reflect these upgrades, therefore it is necessary to use the Sanden Model Number located on the compressor label.
A/C Compressor Clutch Plate Removal Note
Refer to illustrations at the top of this article for all compressor part and tool call outs.
^ Insert spanner wrench (Mastercool tool No. 90901 or equivalent) into clutch front plate (18) of compressor.
^ Hold plate (18) stationary with spanner and remove 19 mm hex nut (19) from compressor shaft with 19 mm socket wrench.
^ Remove clutch front plate (18) with front plate puller (Mastercool tool No. 90902 or equivalent).
^ Remove bearing dust cover, if equipped with screwdriver.
Note:
Be careful to avoid distorting dust cover when removing.
^ Remove shaft key (17) by lightly tapping with slotted screwdriver and small hammer.
^ Remove all clutch shims (14, 15, 16) present on compressor shaft.
Compressor Shaft Seal Service
Note:
Shaft seal replacement must be performed on a clean, dry surface. Do not use old parts on the shaft seal assembly. Never touch the shaft seal with your fingers. Oil from skin contact will cause seal deterioration. Always use the metal carrier to handle the seal assembly.
^ Remove felt ring (8) with small screwdriver or 0-ring hook.
^ Remove shaft seal retainer snap ring (7) with snap ring pliers (Mastercool tool No. 90903 or equivalent.)
^ On SD-508 compressors remove shaft seal seat (6) with seal seat remover tool (Mastercool tool No. 90414 or equivalent.)
^ On SD-709 compressors remove shaft seal seat (6) with seal seat remover tool (Mastercool tool No. 91139 or equivalent.)
Caution:
Do not scratch the O-Ring groove. Scratches will cause refrigerant leaks in the O-Ring area.
^ On SD-508 model compressors carefully remove 0-ring (5) from compressor case using 0-ring hook (Mastercool tool No. 90412 or equivalent.)
^ On SD-709 model compressors carefully remove 0-ring from seal seat.
^ Insert shaft seal remover/installer tool (Mastercool tool No. 90906 for Sanden SD-508 or Mastercool tool No. 91138 for SD-709, or equivalent) onto compressor shaft up to the seal assembly.
^ Press down with seal remover/installer tool on seal assembly and twist tool until tool engages slots on seal.
^ Pull out shaft seal assembly (4) with tool.
^ Clean seal cavity thoroughly with a suitable cleaning fluid, blow out cavity with dry pressurized air.
Note:
Insure that all foreign substances are removed from the seal cavity area.
^ Install shaft seal sleeve protector over compressor shaft (Mastercool tool No. 90907 or equivalent)
^ Dip new shaft seal assembly (4) in clean, new refrigerant oil.
Caution:
Do not touch the sealing surfaces of the shaft seal. Skin oil will contaminate the seal and cause it to leak.
^ Engage seal remover/installer (Mastercool tool No. 90906 for Sanden SD-508 or Mastercool tool No. 91138 for Sanden SD-709, or equivalent tools) into slots of shaft seal assembly (4).
^ Insert shaft seal (4) into compressor seal cavity firmly.
^ Twist installer tool in opposite direction to disengage tool from shaft seal.
^ Remove tool and shaft seal protector from compressor shaft.
^ Coat new 0-ring (5) with new clean refrigerant oil.
Caution:
Do not scratch the 0-ring groove. Scratches will cause refrigerant leaks in the seal area.
^ On SD-508 model compressors place 0-ring (5) into 0-ring groove in case using 0-ring hook.
^ On SD-709 model compressors install new 0-ring on new seal seat and coat with clean refrigerant oil.
^ Coat seal seat (6) with clean, new refrigerant oil.
^ Install seal seat (6) with installer/removal tool (Mastercool tool No. 90414 for SD-508 and Mastercool tool No. 91139 for SD-709 or equivalent tools.)
^ Press lightly against seal seat (6) with tool to insure proper seating of seal seat.
^ Install snap ring (7) with snap ring pliers (Mastercool tool No. 90903 or equivalent.) Beveled edge lies outward (toward clutch) and flat side towards compressor.
Note:
It may be necessary to lightly tap the snap ring to securely position it in the snap ring groove.
^ Dip new felt ring (8) into fresh, clean refrigerant oil and install on to compressor shaft.
^ Lightly tap new felt ring (8) into place with small hammer.
Clutch Plate Installation
^ Install shims (14, 15, 16) removed earlier in procedure.
^ Re-install shaft key (17) with small hammer and screw driver.
^ Re-install bearing dust cover, if equipped.
^ Align front plate (18) keyway to compressor shaft key (17) and install front plate (18) onto shaft.
^ Install shaft protector (Mastercool tool No. 90910 or equivalent) onto compressor shaft and tap with small hammer to seat clutch plate (18) onto compressor shaft. Tap until clutch plate has bottomed on shims (14, 15, 16.)
^ Install 19 mm hex nut (19) on to compressor shaft.
^ Insert spanner wrench (Mastercool tool No. 90901 or equivalent) into holes of front clutch plate (18) and hold stationary.
CAUTION:
Use a beam type torque wrench. Damage may result from use of inaccurate "click" wrenches.
^ Tighten hex nut (19.) Tightening Torque: 30-34 Nm, (22-25 ft. lb.)
Note:
The air gap (a) is determined by the spacer shims (14, 15, 16). When installing a clutch assembly, try the original shims first. When installing a new clutch on a new compressor use the 1 mm, 0.5 mm, and the 0.127 mm shims provided in the clutch installation kit. If the air gap does not meet specification, add or remove shims accordingly.
^ Check air gap (a) of clutch with feeler gauge (Mastercool tool No. 91146 or equivalent.) The gap should be 0.400 mm to 0.800 mm (0.016 in. to 0.031 in.)
Note:
If air gap (a) is not consistent around the circumference, lightly pry up on the front face plate at the low spots and lightly tap down on the high spots with a small hammer.
Shaft Seal Replacement
Labor Operation Number: 87 32 21 0
Suggested Repair Time: 55 TU
^ Lubricate all 0-rings with clean refrigerant oil.
^ Wash exterior case of compressor with hot soapy water to remove any CFC residues from the compressor exterior.
^ Dry compressor with dry pressurized air.
^ Install compressor in vehicle.
Note:
Refer to Group 87 of the Repair Manual Microfiche for all mechanical installation instructions including belt tensioning.
^ Remove plugs from A/C lines.
^ Install A/C lines to compressor. Tightening Torque: Suction 35 Nm Discharge 25 Nm
^ Evacuate and charge A/C system.
Evacuate and Charge A/C System
Labor Operation Number: 87 01 61 0
Suggested Repair Time: 75 TU
^ Operate A/C system and verify with leak detector shaft seal does not leak.
Note:
If the front bearing seal still leaks after the new seal has been installed, replace the compressor. No further repairs are possible to the seal, the mating surfaces are damaged beyond repair.