Reassembly

1 The remaining contents of the casing (lower, smaller cog and spring assembly) are now removed. Holding the casing in a metalworking vice, the remnants of the six blind rivets are filed level to the casing and once again carefully centre-punched, followed by drilling with a 4mm drill to a depth of 12mm.

2 The six holes are now tapped to take M5 bolts and the corresponding holes in the covering plate opened up to accept countersunk M5 machine screw heads. The casing is now thoroughly cleaned of swarf. First the lower, smaller cog operating the gear selector mechanism is replaced, followed by drive shaft assembly so the gears line up. Finally, the U-shaped plastic seating and the thin springs are relocated, tensioning the contents inside the unit. This is quite straightforward and does not permit incorrect assembly. All are now coated liberally with marine-grade thick grease.

3 Depressing the red button can now be seen to detach the main shaft cog from engaging with the gear selector cog, allowing the throttle link to swivel in neutral. Closure of the unit is by means of six M5 x 10mm countersunk stainless machine screws plus Loctite adhesive.

4 Re-attach the throttle and gear selector plates with their M6 machine screws and washers.

5 Re-attach the throttle and gear cables then re-install the control unit in the boat.