Isuzu KB P190. Manual - part 254

ENGINE ELECTRICAL   6D – 15 

 

Oil seal 

The oil seal must be replaced with a new one whenever 
the alternator is disassembled. 

 

 

 

 

 

Oil Seal Replacement 

1.  Push the old oil seal from the rear bracket outside 

holes. 

2.  Use the insertion tool to press the new oil seal into 

place. Follow the procedure shown in Figures A, B, C 
and D. 
࡮  Position the oil seal beneath the shaft and the 

guide lip. 

࡮  Position the cradle against the rear cover bosses 

(3 points) so that the E1 and E2 surfaces fit into 
the cradle. Take care not to damage the E1 and 
E2 surfaces. 

࡮  After completing the procedure, carefully check the 

oil seal seating. Be absolutely sure that the seal is 
evenly inserted (no warp) and level with the 
surrounding surfaces. 

Caution 
࡮

࡮

࡮

࡮  Be sure that no foreign material enters the space 

between the oil seal and the rotor shaft surfaces 
during the installation procedure. 

࡮

࡮

࡮

࡮  Take care not to damage the D surface. 
࡮

࡮

࡮

࡮  Under no circumstances may the original oil seal 

be reused. 

࡮

࡮

࡮

࡮  The oil seal must be perfectly flat after being 

pressed into place. If the oil seal is tilted, there will 
be oil leakage. 

 

 

 

 

 

 

 

 

RTW46DSF000101 

6D – 16  ENGINE ELECTRICAL 

 

  

 

RTW46DSH000901 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Vacuum Pump 

Vacuum Pump Disassembly 

1.  Remove the center plate from the vacuum pump 

housing. 

2.  Remove the vacuum pump rotor and the vanes from 

the housing. 

 
 

Inspection 

Vacuum Pump Housing and Center Plate 

Inspect the vacuum pump housing and the center plate for 
excessive wear, abrasion, and scoring. 
If any of these conditions are present, the vacuum pump 
housing and center plate must be replaced. 

 

 

 

 
 

 

Vane 

Inspect the vanes for excessive wear and damage. 
Replace all four vanes if either of these conditions are 
present. 
Never replace only one vane. 

 
 

Rotor 

1.  Inspect the rotor for excessive wear, abrasion, and 

scoring. 
Pay particular attention to the internal spline. 
Replace the rotor if any of these conditions are 
present. 

2.  Inspect the generator rotor shaft splines for backlash.

Replace the rotor if backlash is present. 

 

 

 

      

     

 

RTW46DSH005201 

 

Check Value 

1.  Carefully force the valve from the “B” side as shown in 

the illustration. 
The valve must move smoothly. 
If it does not, the check valve must be replaced. 

2.  Apply compressed air to the “A” side. 
Air Pressure 

kPa  (kg/cm

2

/psi)

98 - 490 (1-5/14 – 71) 

 

Check for air leakage from the check valve. 
If there is air leakage, the valve must be replaced. 

ENGINE ELECTRICAL   6D – 17 

 

  

 

RTW46DSH001801 

Vacuum Pump Reassembly 

1.  Install the vanes to the rotor slits. 

The rounded side of the vanes must be facing the 
rotor housing. 

 

 

 

 

RTW46DSH001901 

 

2.  Install the rotor with the concave side facing the center 

plate. 

 

  

 

RTW46DSH002001 

 

3.  Install the center plate to the rotor housing. 

Be sure to use a new O-ring. 

 

6D – 18  ENGINE ELECTRICAL 

  REASSEMBLY 

 

 

 

 

RTW46DLF000501 

 

 

Reassembly Step 

 

 

 

   1.  Front cover 

 

 

 

   2.  Rear rotor bearing 

 

 

 

   3.  Rotor Assembly 

 

 

 

   4.  Pulley  

 

 

   5.  Rectifier Assembly 

 

 

 

   6.  Stator Assembly 

 

 

 

   7.  Rear cover 

 

 

 

   8.  B Terminal nuts 

 

 

 

   9.  Through bolt 

 

 

 

  10.  O-ring  

 

 

  11.  Vacuum pump