Your 5 speed gearbox has a special 5th gear, laygear, and reverse idler shaft assembled with a modified gearbox main case and a different speedo end casting.
These parts must be removed before the main gearbox cluster can be removed. When a clean work area has been prepared, the removal of the 5th gear and laygear is as follows.
1. Remove the new speedo end casting assembly with the two bearings. These are a slide fit in the casting and are not positively retained.
2. Remove taper bearing No LM11749 off the 5th gear shaft along with the needle roller bearing carrier from the bore of the 5th gear, leaving the gear loose on the shaft.
3. Remove diff and housing as per workshop manual, turn the selector rod at base of diff housing area anti clockwise-and with the spool pull out as far as possible...
Your 5 speed gearbox has a special 5th gear, laygear, and reverse idler shaft assembled with a modified gearbox main case and a different speedo end casting.
These parts must be removed before the main gearbox cluster can be removed. When a clean work area has been prepared, the removal of the 5th gear and laygear is as follows.
1. Remove the new speedo end casting assembly with the two bearings. These are a slide fit in the casting and are not positively retained.
2. Remove taper bearing No LM11749 off the 5th gear shaft along with the needle roller bearing carrier from the bore of the 5th gear, leaving the gear loose on the shaft.
3. Remove diff and housing as per workshop manual, turn the selector rod at base of diff housing area anti clockwise-and with the spool pull out as far as possible to enable locking the synchro hubs in 2 gears, preferably 1st and 4th to undo all relevant mainshaft nuts.
4. Manually slide back the 5th gear outer track as if selecting reverse gear this will expose the splined thrust washer between 5th gear and the 5th gear synchro hub (this is visible through the synchro ring location cut out in the inner synchro hub).
5. Slide the splined thrust washer back towards 5th gear, this will expose the thrust washer locating pin (visible through one of the three location out-outs in the hub). Remove the pin out through the top or by rotating the shaft as necessary to allow the pin to drop from its drilled hole. Remove pin from the gearbox and store safely. Remove layshaft retaining plate held with socket screw-use a 3/l6” Allen key, withdraw laygear stub axle from flywheel end of transmission. Insert a 13mm hex key into the layshaft hole and undo the socket nut. As the nut is undone the 5th gear shaft will move towards the speedo casting end of the gearbox. When the nut disengages the thread, the 5th gear shaft can be pulled from the gearbox.
6. Support 5th gear and remove the 5th gear shaft from the gearbox through the speedo casting aperture.
7. Remove 5th gear, 5th gear synchro hub, splined thrust washer, counter bored spacer and taper bearing LMIZ749 through the top of the gearbox.
8. Replace laygear stubaxle and the 5th gear shaft back through the gearbox casing and into the laygear assembly. Tap off the 2 bearings on the end of the 5th gear output bell, slide back the output bell which is against the pinion until it is engaged only on the lock nut spline. Place a 22mm socket on the end of the output bell hexagonal drive and undo anticlockwise this will then allow the splined spacer and pinion to be removed.
9. Pull out the laygear stubaxle and 5th gear shaft from the laygear and lift out the laygear assembly from the gearbox ease with thrust washer. The only purpose of the thrust washer is to control the bearings in the cud of the laygear, the position of the Iaygear within the casing is now being controlled by the taper roller bearings referred to earlier and set when originally built.
10. It is important to note the assembly order of the parts fitted to the 28mm bearing bore. Particularly, this order is referred to in the assembly instructions.
11. Remove the nyloc nut from the end of the reverse gear shah, unbolt the centre web bearing carrier bracket and remove from the gear case.
12. Slide the reverse idler shaft towards the transfer gear end of the main case to expose the “E” clip in its groove near the end of the shaft. (at this point reverse gear position should still be engaged). Remove the clip (store it safely) and extract the reverse idler shaft out through the speedo casting aperture. Remove the reverse idler gear. You should now be left with your main original gearbox cluster for removal and refer to workshop manual if required.
This fitting instruction is for parts:
MSG04
MSG05
MSG06
MSG07
MSG08
MSG09
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