2004 ISUZU TF SERIES check engine

ENGINE ELECTRICAL 6D – 13
STATOR COIL ASSEMBLY
1. Check for continuity across the stator coils.
If there is no continuity, the stator coils must be
replaced.
Resistance Between The Terminal “N” and the Coil Ends
(Reference) ohms
Standard 0.1

066RY00022 2. Check for continuity between each stator coils and the
stator core.
If there is continuity, the stator coils must be replaced.
066RY00023


RTW46DSH004801
BRUSH
Measure the length of the brush. If abrasion has reduced
the brush length to less than 6.5 mm, the brush must be
replaced with a new one.
A wear line is inscribed in the brush. If the line is not
visible, the brush must be replaced.
Brush Length (Reference) mm (in)

Standard Limit
25 (1.0) 6.5 (0.25)



RTW46DSH001201
Rectifier


Tester wire
E BAT
U, V, and WN ⊕  U, V, and WN⊕ 
⊕ ----- Conductivity ⊕ ----- No
conductivity

No
conductivity -----
 Conductivity -----
Negative side diode check Positive side diode check

6D – 14 ENGINE ELECTRICAL
RECTIFIER ASSEMBLY



RTW46DSF000301

1. Voltmeter
2. Switch 1
3. DC regulated power supply
4. Lamp 2
5. Lamp 1
6. Switch 3
7. Switch 2
8. Pulse generator
9. Output signal

Test circuit
Refer to the judgment criteria shown in the Table below.
Carefully check Items 1~5. If all the items are OK, the IC
regulator is normal.

Circuit components
1 DC regulated power supply 0~20 volts variable with output of 1 ampere or more
2 Lamps (2) 12 volts, 1.4~3.4 watts
3 Switches (3) -----
4 DC voltmeter 0~30 volts, 0.5 grade
5 Pulse generator (Oscillator) 5~30 volt output at a frequency of 1kHz

Judgment criteria
Lamp condition
No. Switch
1 Switch
2 Switch
3 Voltmeter
reading
Lamp 1 Lamp 2Remarks
1 ON OFF OFF On
(dim) ON Initial excitation check
2 ON ON OFF 12V
On or
flashingFull excitation check
3 ON ON OFF 16V Off or
on (dim)OFF
Lamp 1 off or dimly lit when the
voltmeter shows less than 12 volts or
16 volts
4 OFF ON OFF 12V On or
flashingStator and brush separation check
5 ON ON ON 18V On ON
Excess voltage check

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 – 21




RTW06DSH000201











9. Through Bolt
1. Place a pilot bar into the through bolt hole to align the
front cover and the rear cover.
2. Install the through bolts and tighten them to the
specified torque.
Through Bolt Torque Nm (kgm/lbft)
3.1  3.9 (0.32  0.41 / 2.6  3.5)


11. Vaccum Pump
To install the generator -

1. Note the direction of the arrow on the vacuum pump.
2. Look forward from the base of the arrow to locate the
3 generator fixing points.
3. Twist the fixing points down and to the left to align
them with the middle of the center plate and the rotor.




RTW46DSH006101
Install vanes into slits in rotor.
The vanes should be installed with the chamfered side
facing outward.



RTW46DSH002401
Install the vacuum pump housing.
Make sure that the O-ring is not projecting beyond the
slots of the center plate.
Take care so that no scratching takes place on the vane
resulted by contact with the housing.



RTW46DSH002501













Install the housing in the generator and fix it with the three
bolts.
Supply engine oil (5cc or so) from the oil port and check
that the generator pulley can be turned smoothly with your
hand.
Generator Housing Bolt Torque Nm (kgm/lbft)
5.9  6.9 (0.6  0.7 / 5.2  6.1)

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.

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.