Plate Movement

Fig. 9 Air flow sensor plate side clearance:

Fig. 6 Air flow sensor plate rest position:

To prevent fuel from being injected when sensor plate is lifted, ensure that ignition switch is in off position.
1. Remove rubber bellows between air flow sensor and throttle housing.
2. Lift up on sensor plate using pliers on center stud or a magnet.
3. As lever arm is lifted, steady resistance should be felt from dampening of the control plunger.
4. As lever arm is pushed down suddenly, no resistance should be felt, as lever arm is not acting on plunger.
5. Check that clearance between edge of sensor plate and venturi wall is uniform, Fig. 9.
6. Check rest position of sensor plate, Fig. 6.
7. Top of plate should be even with, to 0.02 in. (0-0.5 mm) below, lower edge of venturi.
8. If clearances or lever arm operation are not as specified, air flow sensor must be removed and disassembled, proceed to step 9. If the clearances and arm operation are good, test is over.
9. Remove mixture control unit, lower plastic section, and fuel distributor.
10. Remove retaining screws and sensor plate.
11. Remove circlips from lever seating, shims, rubber seals, spring and balls.
12. Remove counterweight retaining screw and press out pivot.
13. Remove lever with counterweight and adjustment arm.
14. Knock out mixture adjustment plug. Plug must be installed after fuel-air mixture is set.
15. To install, fit counterweight to lever but do not completely tighten screw.
16. Install adjustment arm in lever in such a way as to expose socket head screw on adjustment arm for viewing.
17. Grease both bearings with Bosch FT2V2 or equivalent silicon grease.
18. Install lever with adjustment arm in air flow sensor housing and mount pivot.
19. Grease the balls and install them together with springs, seals, shims, and circlips. Install the spring on side with longest bearing seat. The circlips are pressed and should be installed with the sharp edge facing out.
20. Install sensor plate in the centering tool and place both tool and plate in venturi.
21. Center lever so that threaded hole is aligned with hole in sensor plate.
22. Torque counterweight retaining screw to 3.4-3.8 ft. lbs. (4.7-5.3 Nm).
23. Install sensor plate retaining screw and torque to 3.6-4.0 ft. lbs. (5.0-5.5 Nm). Check that lever can be moved without resistance.
24. Adjust sensor plate rest position by bending the wire loop on stop bracket beneath air flow sensor.
25. Preset position of adjustment arm as follows:
a. Using a depth gauge, measure the distance between joint surface of fuel distributor (across screw holes) and the needle bearing roller.
b. Adjust the dimension to 0.71-0.75 inches (18-19 mm), turn the mixture adjustment screw with an Allen key.
26. Install O-ring and distributor. Torque screws to 2.3-2.7 ft. lbs. (3.2-3.8 Nm).
28. Install lower section of air flow sensor together with gasket.
29. Install mixture control unit in vehicle. Make fine adjustment to mixture control with CO meter.