Caution! The maximum engine speed adjustment screw is sealed by the manufacturer at the factory. Do not break the seal if the vehicle is still under warranty. This adjustment requires the use of a tachometer - see Section Removal, installation, inspection and adjustment of the thermal actuator and fast idle cable.
Note: The following procedure only applies to models with the F8Q 620 engine (bosch fuel pump). On F8Q engines equipped with a Lucas fuel pump, adjustment can only be made on a test bench. On F9Q engines, maximum engine speed is controlled by the electronic injection module.
1. Warm up the engine to normal operating temperature.
2. Ask an assistant to press the accelerator pedal all the way down and make sure that the maximum engine speed corresponds to the data given in Specifications. Do not allow the engine to run at maximum speed for more than two or three seconds.
3. If adjustment is necessary, turn off the engine, loosen the lock nut and turn the maximum speed adjustment screw. Finally, tighten the lock nut (refer to the accompanying illustration).
4. Repeat the procedure from paragraph 2 to check the adjustment.
5. Turn off the engine and disconnect the tachometer.