Isuzu KB P190. Manual - part 256

ENGINE ELECTRICAL   6D – 23 

 

  DISASSEMBLY 

 

 

 

 

RTW460LF000201 

 

Disassembly Step 

 

 

 

   1.  Lead wire 

 

 

14.

Armature 

   2.  Bolt  

 

15.

Bolt 

   3.  Magnetic switch assembly 

 

 

16.

Bearing retainer 

   4.  Torsion spring 

 

 

17.

Pinion assembly 

   5.  Plunger 

 

 

18.

Pinion stopper clip 

   6.  Dust cover 

 

 

19.

Pinion stopper 

   7.  Magnetic switch 

 

 

20.

Return spring 

   8.  Screw  

 

 

21.

Pinion shaft 

   9.  Through bolt 

 

 

22.

Clutch 

  10.  Rear cover 

 

 

23.

Dust cover 

  11.  Motor assembly 

 

 

24.

Shift lever 

  12.  Brush holder 

 

 

25.

Gear case 

  13.  Yoke  

 

 

 

6D – 24  ENGINE ELECTRICAL 

 

  

 

RTW46DSH002601 

Important Operations 

1. Lead 

Wire 

Disconnect the lead wire at the magnetic switch. 

 

  

 

RTW46DSH002701 

 

3.  Magnetic Switch Assembly 

Remove the magnetic switch bolts, then remove the 
switch from the shift lever. 

 

  

 

RTW46DSH002801 

 

Remove the torsion spring from the magnetic switch. 

 

  

 

RTW46DSH002901 

 

8. Through 

Bolt 

9. Screw 
10. Rear Cover 

Remove the through bolts, then remove the rear cover. 

 

  

 

RTW46DSH003001 

 

11. Motor Assembly 

Remove the four brushes from the brush holders. 

 

ENGINE ELECTRICAL   6D – 25 

 

  

 

RTW46DSH003101 

 

Remove the yoke along with the armature and the brush 
holder from the gear case. 
Remove the brushes and commutator carefully so as not 
to allow them in contact with the adjacent parts. 

 

  

 

RTW46DSH003201 

 

12. Brush Holder 
13. Yoke 
14. Armature 

Remove the brush holder and pull out the armature 
assembly free from the yoke. 

 

     

 

RTW46DSH003301 

 

16. Bearing Retainer 
17. Pinion Assembly 
23. Dust Cover 
24. Shift Lever 
25. Gear Case 

1.  Remove the bearing retainer. 
2.  Remove the pinion from the gear case. 

 

  

 

RTW46DSH003401 

 

3.  Use a screwdriver to remove the stopper clip. Then 

disassemble the pinion assembly. 

 

6D – 26  ENGINE ELECTRICAL 

  INSPECTION AND REPAIR 

Make the necessary adjustments, repairs, and part replacement if excessive wear or damage is discovered during 
inspection. 
 

ARMATURE 

1.  Measure the commutator run-out. 

Replace the commutator if the measured run-out 
exceeds the specified limit. 

Commutator Run-Out 

mm (in)

Standard Limit 

0.05 (0.002) 

0.2 (0.008) 

 

  

 

RTW46DSH003501 

 

 

 

 

 

 

 

 

 

 

 

 

2.  Check the commutator mica segments for excessive 

wear. 

3.  Measure the mica segment depth. 
Mica Segment Depth 

mm (in)

Standard Limit 

0.5 

∼ 0.8 (0.020 ∼ 0.030) 

0.2 (0.008) 

 

065RY00025

 

 

 

 

 

 

 

 

If the mica segment depth is less than the standard but 
more than the limit, the commutator may be reground. 
If the mica segment depth is less than the limit, the 
commutator must be replaced. 

 

 

 

4.  Measure the commutator outside diameter. 
Commutator Outside Diameter 

mm (in)

Standard Limit 

36.5 (1.44) 

35.5 (1.40) 

 

 

 

 

 

If the measured outside diameter is less than the specified 
limit, the commutator must be replaced. 

065RY00026

 

 

 

 

 

RTW46DSH003601 

 

5.  Use a circuit tester to check the armature for 

grounding. 

1 

Hold one probe of the circuit tester against the 
commutator segment. 

2 

Hold the other circuit tester probe against the 
armature core. 

 

If the circuit tester indicates continuity, the armature is 
grounded. 
The armature must be replaced.