Repairing air-conditioner magnetic clutch -N25 ("Denso" compressor) — AUDI

Notes:

Do not open refrigerant circuit to repair air-conditioner magnetic clutch (detach compressor from bracket).
Removing and installing ribbed belt.

4 cyl. engine =>Page
87-32
.
6 and 8-cyl. petrol engine

=> Relevant Engine Workshop Manual, Mechanical Components; Repair group 13
Relevant Engine Workshop Manual, Mechanical Components

6 cyl. diesel engine =>Page
87-35

Mark the direction of rotation before removing the ribbed belt.

Bolt
Tightening torque 15 Nm.
Unfastening and tightening =>Fig.
1
.

Detach clutch plate
Detaching =>Fig.
2
.

Spacers
To adjust gap between clutch disc and pulley.
Gap dimension:
0.4 to 0.6 mm.
Checking and adjusting gap width => Fig.
4

Circlip
Renew
Install on correct side (flat side facing compressor).
Ensure correct seating in groove.

Belt pulley

Note:

If belt pulley has seized up, detach it using, for example, a two or three-arm puller while taking care not to damage the pulley.

Circlip
Renew
Install on correct side (flat side facing compressor).
Ensure correct seating in groove.

Solenoid
Installing => Fig.
3

Notes:

An overheating fuse is installed in the solenoid. The overheating fuse interrupts the solenoid as soon as the air conditioner magnetic clutch becomes too hot (e.g. due to a stiff compressor).
The familiar protective diode -J201 has already been integrated in this solenoid (reduces the voltage peaks which may occur when the air conditioner magnetic clutch is disengaged).

Bolt
Compressor ("Denso")

Fig.:1
Loosening and tightening hexagon bolt.

Tightening torque 15 Nm.

Note:

Use commercially available strap wrench -A- (with fabric strap) to provide support at the clutch plate.

Fig.:2
Detaching clutch plate.

Lever off carefully with screwdrivers.

Note:

Use a two-arm or three-arm puller if the clutch plate is seized.

Fig.:3
Installing solenoid.

Install lug -A- in recess -B-.

Fig.:4
Checking and adjusting gap width

Use depth gauge -C- to measure dimension "1" between belt pulley and clutch plate at three locations.
Apply 12 V to the solenoid (positive at one-way connector -A-, earth at compressor housing -B-).
Use depth gauge -C- to measure dimension "2" between belt pulley and clutch plate.

Gap width (difference between dimension "1" and "2"):
0.4 to 0.6 mm.

Notes:

The gap width must be within the tolerance over the entire periphery.
The gap width can also be measured with the compressor installed.
If the gap width is not within the permissible range, remove the clutch disc and set the gap width by removing or inserting spacers.