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Maintenance - Converter oil - Operate the system - Hove it works - Specifications - Trouble shooter - Stall test - Control valve - The nut - Electric - Adj. clutchservo - Adj. gearlever - Exploded view - Funciona mal el Saxomat? - Part numbers - Fix AFT leaking

The system

In place of the four forward speeds of the standard manual transmission with clutch pedal, the Semi-Auto allows the driver to work a clutch pedal, and in each drive range you have available a wider range of speed than the single gear in the manual transmission would have provide.Since only occasional changes from one range to another are required, the drive is like heaven!

With the Semi-Auto you operate the hand level only about a tenth as often as you would have to shift gears in a car with a manual transmission.
So what are you waiting for?
Run out and fine one, and let us know about your new car!

The way it's work
A 3-speed gearbox of conventional design, a clutch of conventional design and a torque converter are all married together.Gears are changed by a conventional gear lever.The gear lever, however,is connected to the clutch in such a way that soon as the lever is moved longitudinally(i.e in gear selection direction) the clutch disengages.
The torque converter operates to transmit power when the engine is turning above idling speed and so therefore acts as a moving off clutch.It also acts as a form of `slip` between engine and gear-In other words when engine load is higher-such as when moving from rest or uphill-the engine speed can increase to impart more power even though the vehicle remains in the same gear at the same speed.This enables the same as 2nd,3rd and top of a conventional 4 speed manual gearbox.
If the torque converter is called upon to 'slip' too mutch - for example when driving up a long hill in top gear, the oil will overheat.When this happens a temperature sensitive warning light on the dashboard lights up and indicates that a lower gear should be selected. Lowest gear is adequate for all normal conditions and no warning light for the low range is installed.

The operation of the clutch is pneumatic via a control valve and servo.Vacuum is draw from the engine intake manifold and there is also a vacuum tank.The control valve is fitted on the left side of the engine compartment and the vacuum tank under the left rear wing.The vacuum control valve is actuated by a solenoid switch and in turn is actuated by a special switch incorporated in the gear lever base.As soon as the gear lever is moved forward or backwards the switch contacts close,and the solenoid operates.In addition there is a second switch.This acts as a starter inhibitor witch avoids the engine being started with a gear engaged.It also prevents the clutch from engaging again during the brief period of lateral movement of the lever from one range to another through neutral.
The control valve also incorporates a device to regulate the speed with which the clutch engages.In accelerating circumstances (throttle open)the operation of the servo is quicker than would be possible whit a foot pedal change.In decelerating conditions(throttle closed)the control valve controls the servo to operate less quickly.This enables the clutch to re-engage smoothly an without snatch
Oil for the torque converter is circulated by a pump from the converter and through a reservoir tank which is mounted under the right rear wing.The pump is fitted on the end of the engine oil pump shaft.This oil circulation serves to cool the oil as well as maintain a constant pressure,(by means of a restriction in the return line).A relief valve is incorporated in the pump to limit maximum pressure.


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