Olymat (Saxomat) automatic Clutch

Operating principle and pictures

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The Olymat (Saxomat) clutch is a combination of  two single dry plate clutches:  one is operated by centrifugal force and utilises a bronze friction material and another is a normal type with asbestos material and is operated by a release bearing, a clutch lever and a vacuum actuator. The illustration to the left shows the high-rpm situation vhere the centrifugal clutch is engaged. The illustration to the right shows the low-rpm situation where the centrifugal clutch is released.

The purpose of the clutch control system is to release the clutch whenever the gearlever  (1) is operated and  reengage the clutch,  when a new gear has been selected, and the accelerator pedal is depressed. Vacuum is supplied from the intake manifold and stored in  a  reservoir.  When the gearlever is touched electric current is supplied to the solenoid in the controlvalve (2). Vacuum is transferred to the vacuum diaphragm actuator (3) which pulls the clutch lever and releases the clutch. The diaphragm-valve-system  at the right end of the control valve (2)  ensures a controlled vacuum release and thereby a soft reengagement of the clutch.  The thin hose connection to the upper part of the carburettor  signals a  hard depressed accelerator  which hastens the clutch take-up.

The Fichtel & Sachs Saxomat clutch control valve mounted in Opel Rekord P2 1961


The pull rod from the vacuum actuator is seen under the clutch control valve


Vacuum actuator from scrapped car. The pull rod normally attached to the hexagon in the center is broken off.


Pressure plate and friction disk belonging to the centrifugal clutch. Note the 6 centrifugal weights.

 The bronze padding on the friction disk is completely worn down.


Pressure plate and friction disk seen from other side. Both are worn down.