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Detaching and attaching clutch plate > < Detaching/attaching pulley

A4 Mk3

Replacing pulley with magnetic clutch N25
Replacing pulley with magnetic clutch -N25-
  Note
t  If the pulley overload safeguard has been tripped, check the freedom of movement of the air conditioner compressor before replacing the pulley. Replace the entire air conditioner compressor if it is stiff.
t  It is not necessary to dismantle the air conditioner compressor from the engine to detach the pulley → Chapter. Depending on the engine version, it may however be necessary to unfasten the lock carrier from the vehicle and pull it forwards slightly (to make room) → General body repairs, exterior; Rep. gr.50.
t  Various pulley designs (with different diameters) may be fitted depending on the type of air conditioner compressor and the engine version → Electronic parts catalogue.
t  The pulley and magnetic clutch are supplied as one replacement part with one part number. The pulley and drive plate may be held together by a bolt, which is not required and can therefore be disposed of. This bolt is used at the factory to apply a pre-determined quantity of a specific grease to the thread of the drive plate. This quantity of grease is sufficient for once-only screwing of the drive plate onto the compressor shaft (following unscrewing, drive plates are therefore not to be re-used) → Electronic parts catalogue.
   
1 - Cap
q   Not always fitted
2 - Clutch plate
q   Replace
q   Screwed to the air conditioner compressor drive shaft.
–  Clean the contact surfaces of the clutch plate and pulley before screwing on
–  Clean the thread of the compressor shaft before screwing on the clutch plate
–  After tightening, check and if necessary correct the gap between the pulley and clutch plate → Chapter
  Note
The thread of the new clutch plate is pre-greased at the factory with a pre-determined quantity of a specific grease.
q   Different versions → Electronic parts catalogue
q   With overload safeguard; tripped in the event of excessive torque (e.g. stiff air conditioner compressor) and the pulley just free-wheels without driving the air conditioner compressor with the magnetic clutch -N25- activated.
Detaching/attaching
–  To detach, hold the compressor shaft -C- in position and use a suitable tool to turn the clutch plate in arrow direction (anti-clockwise) as described for the drive plate on an air conditioner compressor with no magnetic clutch → Chapter
q   Tightening torque 30 Nm
3 - Plate
4 - Spacer
q   For setting the gap between the clutch plate and pulley
q   Checking gap → Chapter
5 - Circlip
q   Replace
q   Ensure correct positioning (flat side facing air conditioner compressor)
q   On fitting the circlip, take care not to bend it open more than necessary for installation.
–  Ensure correct insertion of the circlip. The bevelled side -A- faces away from the air conditioner compressor (flat side faces compressor).
6 - Pulley
q   The pulley is sensitive to impact and should therefore be treated with care.
q   Clean the air conditioner compressor flange before fitting the pulley.
q   Different versions (depending for example on type of engine) → Electronic parts catalogue
q   If the pulley cannot be detached by hand from the air conditioner compressor flange, refer to → Chapter
7 - Circlip
q   Replace
q   Ensure correct positioning (flat side facing air conditioner compressor)
q   On fitting the circlip, take care not to bend it open more than necessary for installation.
–  Ensure correct insertion of the circlip. The bevelled side -A- faces away from the air conditioner compressor (flat side faces compressor).
8 - Solenoid
q   Pay attention to correct positioning of the holder for the cable -B- on installation.
q   Depending on the version, the connector -D- may be attached to the air conditioner compressor with a holder
9 - Air conditioner compressor
q   Different models may be fitted depending on the engine version and country version of the vehicle → Electronic parts catalogue.
q   Clean the air conditioner compressor flange before fitting the pulley.
q   Clean the thread of the compressor shaft and apply a small quantity of grease to the thread.

   

Detaching and attaching clutch plate > < Detaching/attaching pulley