shogun
07-15-2009, 08:45 PM
http://www.zf.com/media/media/document/brands/sachs/sitematrix/clutches/general/englisch/0032004_SITIP001.pdf
Important Service Bulletin Fan clutches: Function and handling
Hints for experts
Overview
The SACHS fan clutch assists the engine to maintain its correct operating temperature. When the engine temperature exceeds a
certain level, the fan clutch is activated causing additional air flow through the radiator. The fan clutch is activated when hot air passes over a bi-metal strip 1 on the fan clutch, causing deformation of the bi-metal strip which activates the control pin 2.
The control pin opens the valve 3 allowing silicone oil 4 to enter the drive chamber of the fan clutch. The temperature controls the speed of the fan clutch i. e. higher temperature causes higher
speed. As temperature decreases, so does the speed of the fan clutch.
Transport and Storage
To ensure proper function of the fan clutch we recommend that these instructions be followed. It is most important that the fan clutch be
positioned correctly during transportation and storage. Please note the arrow on the fan clutch package. The fan clutch should be
stored either vertically but preferably flat with the arrow pointing up. This is to ensure that silicone oil does not leak past the control pin seal. Should a small amount of oil leak past the
control pin seal due to incorrect storage, the fan clutch will still perform correctly.
Attention:
Fan clutches must be stored flat in the box with the arrow pointing up.
Warning: Please note that the bi-metal strip on the front of the clutch has been calibrated to perform at a particular temperature range. Changing the position of this strip will change the
performance of the fan clutch.
avoid injury – keep clear of fan and pulleys when engine is
running.
Service information
Fan clutches are often replaced even though they are performing correctly. In order to diagnose a cooling system problem, it is
recommended that the following be checked:
Check the coolant level.
Check the temperature gauge.
Check that radiator fins are free from dirt and insects.
Check the proper operation of the thermostat.
Check the fan belt.
Check the operation of the water pump.
Check if sufficient hot air can flow through the radiator to activate the fan clutch.
Check for blockages inside the radiator preventing flow of coolant.
Check that the fan is the correct type and undamaged.
Noise generated by the AC clutch or by the engine should be investigated.
Fitting Instructions:
Adjust water pump drive belt to specification (do not overtighten).
Unscrew fan clutch from spindle 6.
Caution Mercedes Benz applications. Check the direction of rotation of the fan. The direction of rotation is also shown on the mounting flange. The engine side of the fan clutch required to be mounted to the spindle is marked accordingly. Radiator fins are of solid material 7.
1) An anti clockwise (left hand) rotating clutch has a right hand threaded nut.
2) A clockwise (right hand) rotating clutch has a left hand threaded nut.
Note:
To ensure that the correct part number is fitted for the vehicle application see application list.
All bolts should be tightened to recommended torque (MB 10 Nm / BMW 12 Nm).
(Mercedes Benz mark „Vorne Front“ in the direction of travel).
Tighten the fan clutch onto spindle with the specified torque
(DB 45 Nm / BMW 40+10 Nm).
Important Service Bulletin Fan clutches: Function and handling
Hints for experts
Overview
The SACHS fan clutch assists the engine to maintain its correct operating temperature. When the engine temperature exceeds a
certain level, the fan clutch is activated causing additional air flow through the radiator. The fan clutch is activated when hot air passes over a bi-metal strip 1 on the fan clutch, causing deformation of the bi-metal strip which activates the control pin 2.
The control pin opens the valve 3 allowing silicone oil 4 to enter the drive chamber of the fan clutch. The temperature controls the speed of the fan clutch i. e. higher temperature causes higher
speed. As temperature decreases, so does the speed of the fan clutch.
Transport and Storage
To ensure proper function of the fan clutch we recommend that these instructions be followed. It is most important that the fan clutch be
positioned correctly during transportation and storage. Please note the arrow on the fan clutch package. The fan clutch should be
stored either vertically but preferably flat with the arrow pointing up. This is to ensure that silicone oil does not leak past the control pin seal. Should a small amount of oil leak past the
control pin seal due to incorrect storage, the fan clutch will still perform correctly.
Attention:
Fan clutches must be stored flat in the box with the arrow pointing up.
Warning: Please note that the bi-metal strip on the front of the clutch has been calibrated to perform at a particular temperature range. Changing the position of this strip will change the
performance of the fan clutch.
avoid injury – keep clear of fan and pulleys when engine is
running.
Service information
Fan clutches are often replaced even though they are performing correctly. In order to diagnose a cooling system problem, it is
recommended that the following be checked:
Check the coolant level.
Check the temperature gauge.
Check that radiator fins are free from dirt and insects.
Check the proper operation of the thermostat.
Check the fan belt.
Check the operation of the water pump.
Check if sufficient hot air can flow through the radiator to activate the fan clutch.
Check for blockages inside the radiator preventing flow of coolant.
Check that the fan is the correct type and undamaged.
Noise generated by the AC clutch or by the engine should be investigated.
Fitting Instructions:
Adjust water pump drive belt to specification (do not overtighten).
Unscrew fan clutch from spindle 6.
Caution Mercedes Benz applications. Check the direction of rotation of the fan. The direction of rotation is also shown on the mounting flange. The engine side of the fan clutch required to be mounted to the spindle is marked accordingly. Radiator fins are of solid material 7.
1) An anti clockwise (left hand) rotating clutch has a right hand threaded nut.
2) A clockwise (right hand) rotating clutch has a left hand threaded nut.
Note:
To ensure that the correct part number is fitted for the vehicle application see application list.
All bolts should be tightened to recommended torque (MB 10 Nm / BMW 12 Nm).
(Mercedes Benz mark „Vorne Front“ in the direction of travel).
Tighten the fan clutch onto spindle with the specified torque
(DB 45 Nm / BMW 40+10 Nm).