Isuzu KB P190. Manual - part 1172

7B1-82     MANUAL TRANSMISSION 

 13. Use screw drivers between the reverse gear and the

bearing plate to remove the Rev-5th synchronizer
assembly together with the reverse block ring and
reverse gear. 

  

226RS010

14. Remove the needle bearing. 

 

15. Use the torx bit wrench (T- 45) 5-8840-0047-0 to 

remove the bearing plate and screw from the
intermediate plate. 

 

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16. Use the snap ring pliers (1) to remove the mainshaft

bearing snap ring (2). 

 

 

  

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 17. Hold the snap ring open with the pliers. 

Push the intermediate plate toward the rear of the 
transmission to remove it. 

The bearing snap ring will come free. 

 

Inspection and Repair 

Refer to Top Gear Shaft, Main Gear Shaft, and Counter
Gear in this section for inspection and repair. 

 

Reassembly 

  1. Mesh the counter gear with the mainshaft assembly.

Set the holding fixture 5-8840-2160-0 to the 
mainshaft and the counter gear and then install it on 
the base 5-8840-0003-0. 

Install the intermediate plate on the gear assembly.

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MANUAL TRANSMISSION     7B1-83 

  2. Install the bearing snap ring. 

 3. Apply recommended thread locking agents

(LOCTITE 242) or equivalent to each of the bearing
plate screw threads. 

Install the bearing plate and screw. 

Tighten the screws to the specified torque by using
torx bit wrench (T- 45) 5-8840-0047-0. 

Torque: 15 N

⋅⋅⋅⋅m (1.5 kgf⋅⋅⋅⋅m/11 lb⋅⋅⋅⋅ft) 

 

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  4. Install the needle bearing, reverse gear and reverse

block ring. 

 

 5. Assemble the rev-5th synchronizer assembly by 

performing the following steps. 

1.  Turn the clutch hub face (1) toward the sleeve 

groove (2) (rear side) on the outer 
circumference. 

2.  Check that the inserts (3) fit snugly into the 

clutch hub (5) ring insert grooves. 

3.  Check that the inserts springs (4) are fitted to 

the inserts as shown in the illustration. 

4.  Check that the clutch hub (5) and the sleeve (6) 

slide smoothly. 

5. Install the synchronizer assembly to the 

mainshaft. 

The clutch hub face with the heavy boss must be 
facing the reverse gear side. 

  

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7B1-84     MANUAL TRANSMISSION 

 6. Mesh the 1st-2nd and 3rd-4th synchronizers with

both the 1st and 3rd gears (double engagement). 

  

226RS015

This will prevent the mainshaft from turning. 

  7. Install the new mainshaft hub nut. 

Use the mainshaft nut wrench 5-8840-2156-0 to 
tighten the mainshaft nut to the specified torque. 

Torque: 137 N

⋅⋅⋅⋅m (14.0 kgf⋅⋅⋅⋅m/101 lb⋅⋅⋅⋅ft) 

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  8. Use a punch to stake the mainshaft nut. 

  

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  9. Install the needle bearing, 5th block ring, and 5th 

gear. 

 10.  Apply engine oil to the counter reverse gear and the 

reverse gear. 

Install the counter reverse gear to the counter shaft.

The reverse gear projection must be facing the 
intermediate plate. 

  

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MANUAL TRANSMISSION     7B1-85 

 11. Install the counter 5th gear to the counter shaft. 

  

226RS019

 

12. Install the ball bearing and bearing snap ring  by 

performing the following steps: 
•  Select the snap ring which will provide the

minimum clearance between the ball bearing 
and the snap ring. 

  

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•  There are six snap ring sizes available. 

The snap rings are color‐ coded to 
indicate their thickness. 

  

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Ball Bearing and Snap Ring Clearance 

Standard: 0 - 0.15 mm (0 - 0.0059 in) 

 

Snap Ring Availability 

Thickness Color 

Coding 

1.1 mm (0.043 in) 

White 

1.2 mm (0.047 in) 

Yellow 

1.3 mm (0.051 in) 

Blue 

1.4 mm (0.055 in) 

Pink 

1.5 mm (0.059 in) 

Green 

1.6 mm (0.063 in) 

Brown 

•  Use a pair of snap ring pliers to install the snap 

ring to the counter gear shaft. 

The snap ring must be fully inserted into the 
counter gear shaft snap ring groove. 

 13. Assemble the reverse idler shaft, reverse idler gear, 

thrust washer, and idle shaft pin into the reverse 
idler gear assembly. 

The thrust washer should be assembled with the oil 
groove faces to gear side.