Isuzu N-Series. Manual - part 823

7B-62 MANUAL TRANSMISSION (MSB)

Unit Repair

Legend

1. Spring pin

13. Thrust collar

2. Idle gear shaft

14. Front bearing

3. Idle gear

15. Upper cover

4. Needle bearing

16. Plug

5. Lock nut and washer

17. Detent spring

6. Coupling driver

18. Detent pin

7. Front cover

19. Spring pin

8. Rear cover with oil seal

20. Shift rod plug

9. Output shaft

21. Shift rod

10. Rear bearing

22. Shift arm

11. Sleeve

23. Shift rod oil seal

12. Output gear with bushing

24. Gear case

N7A0185E

MANUAL TRANSMISSION (MSB) 7B-63

Disassembly

1. Spring Pin

• Tap the spring pin into the idle shaft.

Spring Pin Remover: 9-8529-2201-0

2. Idle Gear Shaft

• Drive out the idle gear shaft by tapping on its

front end with a suitable bar and hammer.

• Remove the spring pin from the idle gear shaft.

Spring Pin Remover: 9-8529-2201-0

3. Idle Gear
4. Needle Bearing

5. Lock Nut and Washer

• Attach a backing plate to the vice, secure the

coupling driver, and remove the lock nut, spring
washer and plain washer.

6. Coupling Driver
7. Front Cover

8. Rear Cover (with Oil Seal)

• Remove the oil seal from the rear cover.

9. Output Shaft

10. Rear Bearing

• Drive out the output shaft by tapping on its front

end with a suitable bar and hammer.

• Remove the rear bearing from the output shaft.

11. Sleeve
12. Output Gear with Bushing
13. Thrust Collar
14. Front Bearing
15. Upper Cover

N7A0186E

N7A0187E

N7A0188E

N7A0189E

7B-64 MANUAL TRANSMISSION (MSB)

16. Plug
17. Detent Spring
18. Detent Pin

19. Spring Pin

Spring Pin Remover: 9-8529-2201-0

20. Shift Rod Plug
21. Shift Rod
22. Shift Arm

• Move the shift rod (1) rearward by tapping on its

front end. Then, remove the each parts.

23. Shift Rod Oil Seal
24. Gear Case

Inspection and Repair

Make the necessary adjustments, repairs and part re-
placement if excessive wear or damage is discovered
during inspection.
Bearings
Check the each bearing, and replace in either of the fol-
lowing cases.

• Rotation is not smooth.
• Abnormal sound is generated.

N7A0190E

N7A0191E

Legend

1. Spring pin

N7A0192E

N7A0193E

MANUAL TRANSMISSION (MSB) 7B-65

• There is extreme damage or rust.
• Rolling element or rolling contact surface of needle

roller bearing is discolored, extremely worn or pit-
ted.

Gears
Check each gear for the following points. Correct a slight
stepped wear or surface roughness with an oil stone or
pencil grinder, or replace the gear if unrecoverable dam-
age is found.

• Break or damage of tooth.
• Extreme wear of tooth.

Idle Gear Shaft and Output Shaft
Check the shaft external surface for any damage or
wear, and its spline section for wear, damage or bent.
When there is any abnormal condition, or when it is used
excessively beyond a proper use limit, replace it with
new one.
Shift Mechanism
Inspect all disassembled parts for wear, damage or oth-
er abnormal conditions.

• Check the shift rod for wear, bent and damage.
• Check the shift arm for wear or deformation.

• Check the detent spring and detent pin for wear,

weakening and deformation.

• The wear of the shift rod, and the awkward opera-

tion of the gear case.

Sleeve
Check the sleeve for any abnormal conditions.
Correct a slight stepped wear or surface roughness with
an oil stone or pencil grinder, or replace the sleeve if un-
recoverable damage is found.

Ball Bearing Run-out

mm (in)

Limit

0.2 (0.01)

Output Shaft and Output Gear Bushing 
Clearance

mm (in)

Limit

0.2 (0.01)

N7A0194E

Shift Arm Thickness

mm (in)

Standard

Limit

9.0 (0.35)

8.0 (0.31)

N7A0195E