Isuzu KB P190. Manual - part 257

ENGINE ELECTRICAL   6D – 27 

 

  

 

RTW46DSH003701 

 

6.  Use the circuit tester to check the armature for 

continuity. 

1 

Hold the circuit tester probes against two 
commutator segments. 

2 

Repear Step 1 at different segments of the 
armature core. 

 

There should be continuity between all segments of 
the commutator. 
If there is not, the armature must be replaced. 

 

 

  

 

RTW46DSH003801 

 

YOKE 

1.  Use a circuit tester to check the field winding ground. 

1 

Hold one circuit tester probe against the field 
winding end or brush. 

2 

Hold the other circuit tester probe against the bare 
surface of the yoke body. 

 

There should be no continuity. 
If there is continuity, the field coil is grounded. 
The yoke must be replaced. 

 

  

 

RTW46DSH003901 

 

2.  Use the circuit tester to check the field winding 

continuity. 

1 

Hold one circuit tester probe against the “M” 
terminal lead wire. 

2 

Hold the other circuit tester probe against the field 
winding brush. 

 

There should be continuity. 
If there is no continuity, the yoke must be replaced. 

 

6D – 28  ENGINE ELECTRICAL 

BRUSH AND BRUSH HOLDER 

1.  Use a vernier caliper to measure the brush length (four 

brushes). 
Replace the brushes as a set if one or more of the 
brush lengths is less than the specified limit. 

Brush Length 

mm (in)

Standard Limit 

15 (0.59) 

12 (0.47) 

 

  

 

RTW46DSH004001 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

RTW46DSH004101 

 

2.  Use a circuit tester to check the brush holder 

insulation. 
Touch one probe to the holder plate and the other 
probe to the positive brush holder. 
There should be no continuity. 

 
 
 
 
 
3.  Inspect the brushes for excessive wear. 

If the negative brushes have excessive wear, the 
entire brush holder assembly must be replaced. 
If the positive brushes have excessive wear, the entire 
yoke must be replaced. 

 

OVERRUNNING CLUTCH 

1.  Inspect the overrunning clutch gear teeth for 

excessive wear and damage. 
Replace the overrunning clutch if necessary. 

2.  Rotate the pinion clockwise. 

It should turn smoothly. 

3.  Try to rotate the pinion in the opposite direction. 

The pinion should lock. 

065RY00035

 

 

 

  

 

RTW46DSH004401 

BEARING 

Inspect the bearings for excessive wear and damage. 
Replace the bearings if necessary. 

 

ENGINE ELECTRICAL   6D – 29 

  REASSEMBLY 

  

 

 

RTW46DLF000601 

 

 

Reassembly Steps 

 

 

 

   1.  Magnetic switch assembly 

 

 

14.

Pinion stopper 

   2.  Magnetic switch 

 

 

15.

Pinion stopper clip 

   3.  Dust cover 

 

 

16.

Bearing retainer 

   4.  Plunger  

 

17.

Bolt 

   5.  Torsion spring 

 

 

18.

Motor assembly 

   6.  Shift lever 

 

 

19.

Armature 

   7.  Gear case 

 

 

20.

Yoke 

   8.  Dust cover 

 

 

21.

Brush holder 

   9.  Bolt  

 

22.

Rear 

cover 

  10.  Pinion assembly 

 

 

23.

Screw 

  11.  Clutch  

 

24.

Through 

bolt 

  12.  Pinion shaft 

 

 

25.

Lead wire 

  13.  Rerurn spring 

 

 

 

 

 

6D – 30  ENGINE ELECTRICAL 

 

  

 

RTW46DSH005601 

Important Operations 

1.  Magnetic Switch Assembly 

1.  Attach the torsion spring to the hole in the magnetic 

switch as illustrated. 

2.  Insert the shift lever into the plunger hole of the 

magnetic switch. 

 

  

 

RTW46DSH005701 

 

 

 

 

 

 

 

 

 

 

 

 

7. Gear 

Case 

3,8. Dust  Cover 

1.  Install the magnetic switch assembly in the gear case.
2.  Install the dust cover. 
 

Dust Cover Bolt Torque 

N

⋅m (kg⋅m/lb⋅ft)

8 (0.8/5.4) 

 

 

 

 

10. Pinion Assembly 

Apply a coat of grease to the reduction gear and install the 
pinion assembly to the armature shaft. 

065RY00041

 

 

 

   

 

RTW46DSH004501 

 

21. Brush Holders 

1.  Install the brushes into the brush holder with raising 

the spring end of the brush spring. 
Take care not to damage the commutator face. 

2.  Install the brush holder with aligning the peripheries of 

the yoke and the brush holder.