Checking the Mixture Regulator

1. Check the movement of the air flow sensor plate and the metering distributor piston.
2. Disconnect the electrical connectors at the control pressure regulator and at the auxiliary air device.
3. Place the fuel supply circuit under pressure by depressing the switch of the by-pass harness for 10 seconds.
4. Lift the sensor plate slowly, the resistance felt must be identical throughout the entire travel of the sensor plate.
5. Release the sensor plate slowly, the piston should follow the same movement. If during this check, an abnormal resistance is felt, it may come from the seizing of the sensor plate's lever pilot shaft or the piston in its sleeve.
6. Lift the sensor plate and return it rapidly to its rest position.
7. Since the control piston does not move as fast as the sensor plate, you should hear it make contact with the plate lever.
8. If this requirement is fulfilled, the control piston slides freely.
9. If, on the other hand this does not occur, remove the fuel metering distributor.
CAUTION: Take care not to drop the piston while removing the metering distributor.
10. Recheck the free movement of the sensor plate. If it is frozen, replace the airflow sensor plate.