Overhaul

WARNING: The amplifier module is a sealed unit containing Beryllia. This substance is extremely dangerous if handled. Do not attempt to open or crush the module.

OVERHAUL
1. Unclip and remove the cap
2. Fit a new cap if known to be faulty.
3. Clean the cap and HT brush with a lint free cloth.
4. Pull rotor arm from shaft.
5. Fit a new rotor arm if known to be faulty.
6. Remove flash shield, secured by three screws.
7. Fit a new cover if known to be faulty.
8. Remove two screws from vacuum unit securing bracket, disengage vacuum unit connecting rod from pick-up base plate connecting peg, and withdraw vacuum unit from distributor body.
9. Remove two screws and withdraw the amplifier module.
10. Remove the gasket.
11. Remove two screws securing the cast heatsink and remove the heatsink.
12. Use circlip pliers to remove the circlip retaining the reluctor on rotor shaft.
13. Remove the flat washer and then the O-ring recessed in the top of the reluctor,
14. Gently withdraw the reluctor from the shaft, taking care not to damage the teeth.

NOTE: Coupling ring fitted beneath reluctor.

15. Remove three support pillars and cable grommet. Lift out the pick-up and base plate assembly.

NOTE: Do not disturb the two barrel nuts securing the pick-up module, otherwise the air gap will need re-adjustment.

16. Fit a new pick-up and base plate assembly if module is known to be faulty, otherwise check pick-up winding resistance (2k-5k ohm).

RE-ASSEMBLY
1. This is mainly a reversal of the dismantling procedure, noting the following points:
a. Apply 2-3 drops of clean engine oil into the rotor spindle before fitting rotor arm.

b. Apply Omnilube 2 (or equivalent) grease:
- Auto advance mechanism.
- Pick-up plate center bearing.
- Pre tilt spring and its rubbing area (pick-up and base plate assembly).
- Vacuum unit connecting peg (pick-up and base plate assembly).
- The connecting peg hole in vacuum unit connecting rod.






2. Refit pick-up and base plate assembly. Pick-up leads must be prevented from fouling the rotating reluctor. Both leads should be located in plastic guide as illustrated. Check during re-assembly.
3. Slide reluctor as far as it will go on rotor shaft, then rotate reluctor until it engages with the coupling ring beneath the pick-up base plate. The distributor shaft, coupling ring and reluctor are keyed and rotate together. Fit the O-ring, flat washer and retaining circlip.





4. The air gap between the pick-up limb and reluctor teeth must be set to 0.20-0.35 mm (0.008-0.014 in), using a non-ferrous feeler gauge.
5. If adjustment is necessary, slacken the two barrel nuts to set the air gap.

NOTE:
- When the original pick-up and base plate assembly has been refitted the air gap should be checked, and adjusted if necessary.
- When fitting a new assembly the air gap will require adjusting to within the specified limits.

6. Before fitting the amplifier module, apply MS4 Silicone grease or equivalent heat-conducting compound to the amplifier module backplate, the seating face on distributor body and both faces of the heatsink casting.