- Select neutral.
Note: Always use a new circlip (2).
- Introduce actuating shaft into gearbox housing and slip pawl (3) with long lug toward collar and driver (4) with flat toward 5th stage spur gear onto actuating shaft.
- The pawl must be able to engage the selector drum.
Caution: When reassembling, take care not to drop the circlip into the gearbox and make sure that the circlip is correctly seated in its groove.
- Install the circlip (2).
- Press spacer (1) home on shaft.
- Fit a new retaining ring (6) in groove in housing bore.
Cauton: Endplay of actuating shaft must be perceptible before sealing ring (7) is installed.
- Use slip-over sleeve, BMW # 23 4 771, and drift, BMW # 23 4 772, to install new sealing ring (7).
Caution: Check that O-rings on bearing pins (8, 9, 10) are free of damage before installing and apply a light coating of oil to facilitate installation.
- Working from above, insert 4th stage spur gear (4) to engage driver.
- Install bearing pin (10).
- Using adapter, BMW # 00 8 584, and pull rod, BMW # 00 8 581, drive in bearing pin until seated.
- Working from above, insert 3rd stage spur gear (3).
- Install bearing pin (9).
- Using adapter, BMW # 00 8 584, and pull rod, BMW # 008581, drive in bearing pin until seated.
- Working from above, insert 2nd stage spur gear (5).
- Install bearing pin (8).
- Using adapter, BMW # 00 8 584, and pull rod, BMW # 008581, drive in bearing pin until seated
Note: Apply Loctite 243 to threads of screw (11) for plate (12).
- Place plate (12) in position at side of 2nd stage spur gear, press down and install screw (11) to secure.
Caution: When installed, the gear train must rotate easily and evince perceptible endplay and radial play.
Tightening torque:
- Plate, reverser to gearbox (clean thread + Loctite 243) — 10 Nm
Performing a functional check
- Mount shift lever on selector shaft and engage neutral.
- Mount actuating control on actuating shaft of reverser.
- It must be possible to engage the reverser with the gearbox in neutral. If necessary, turn the output shaft to move the gears slightly. If it does not engage, remove reverser and reinstall.
- Remove actuating control for reverser.
Installing cover of reverser
Note: Gear (14) and spring element (13) in cover (2) of reverser must move freely. Check teeth of gear for damage. Replace entire cover (2) if teeth are damaged.
Cauton: When installing cover (2), make particularly sure that:
- Reverser is not engaged 6 BMW cheesehead screws are installed (clearance from generator).
- Reinstall securing screws for reverser cover in their original positions (as marked).
- Coat mating face of cover (2) of reverser with Loctite 574 and install 8 securing screws (1).
- Uniformly tighten securing screws in diagonally opposite sequence.
Tightening torque:
- Cover of reverser to gearbox — 10 Nm
Install actuator unit for reverser
- Install actuating lever (2) in holder (4) with the flats (arrows) toward contacts (5). Turn actuating lever until reverse gear switch moves smoothly in its guides.
- Recess (6) must be toward the gearbox housing.
- Mount fully assembled reverse gear switch on actuating shaft, making sure that recess (6) of retaining plate engages locking pin (3).
Caution: When installing the reverse gear switch, make sure that the rear retaining plate does not slip between gearbox housing and actuating lever.
- Actuating lever (2) must be seated against shaft collar.
- Install new stop nut (1) and tighten.
Tightening torque:
- Reverse gear switch on actuating shaft — 9 Nm