Starter Motor: Testing and Inspection

STARTER INSPECTION

On-vehicle Inspection
1. Verify that the battery is fully charged.

2. The starter is normal if it rotates smoothly and without any noise when the engine is cranked.
- If the starter does not operate, inspect the following:
- Remove the starter, and inspect the starter unit.
- Inspect the related wiring harnesses, the ignition switch, and the transmission range switch (AT).

No-load test
1. Verify that the battery is fully charged.




2. Connect the starter, battery, and a tester as shown in the figure.

3. Operate the starter and verify that it rotates smoothly.
- If the starter does not rotate smoothly, inspect the starter unit.




4. Measure the voltage and current while the starter is operating.
- If not within the specification, replace the starter.

Magnetic Switch Operation Inspection

Pull-out test

NOTE: Depending on the battery charge condition, the starter motor pinion may rotate while in an extended state. This is due to current flowing to the starter motor through the pull-in coil to turn the starter motor, and does not indicate an abnormality.




1. Verify that the starter motor pinion is extended while battery positive voltage is connected to terminal S and the starter body is grounded.
- If the starter motor pinion is not extended, repair or replace the starter.

Return test
1. Disconnect the motor wire from terminal M.




2. Connect battery positive voltage to terminal M and ground the starter body.

3. Pull out the drive pinion with a screwdriver. Verify that it returns to its original position when released.
- If it does not return, repair or replace the starter.

Pinion Gap Inspection




1. Pull out the drive pinion with the battery positive voltage connected to terminal S and the starter body grounded.

CAUTION: Applying power for more than 10 s can damage the starter. Do not apply power for more than 10 s.




2. Measure the pinion gap while the drive pinion is extended.
- If not as specified, adjust with an adjustment washer (between drive housing front cover and magnetic switch).

Pinion gap
AT: 0 mm (0 in)
MT: 0.5 - 2.0 mm (0.02 - 0.07 in)

Starter Inner Parts Inspection

Armature




1. Verify that there is no continuity between the commutator and the core at each segment using a tester.
- If there is continuity, replace the armature.




2. Verify that there is no continuity between the commutator and the shaft using a tester.
- If there is continuity, replace the armature.




3. Place the armature on V-blocks, and measure the runout using a dial indicator.

Runout 0.05 mm (0.002 in) max.




4. Measure the commutator diameter.
- If not within the minimum specification, replace the armature.

Standard commutator diameter 29.4 mm (1.16 in)
Minimum commutator diameter 28.8 mm (1.13 in)




5. Measure the segment groove depth of the commutator.
- If not within the minimum specification, undercut the grooves to the standard depth.

Standard depth 0.4 - O.6 mm (0.016 - 0.023 in)
Minimum depth 0.2 mm (0.008 in)

Magnetic switch




1. Inspect for continuity between terminals S and M using a tester.
- If there is no continuity, replace the magnetic switch.




2. Inspect for continuity between terminal S and the body using a tester.
- If there is no continuity, replace the magnetic switch.




3. Verify that there is no continuity between terminals M and B using a tester.
- If there is continuity, replace the magnetic switch.

Brush and brush holder
1. Verify that there is no continuity between each insulated brush and plate using a tester.
- If there is continuity, replace the brush holder.




2. Measure the brush length.
- If any brush is worn almost to or beyond the minimum specification, replace all of the brushes.

Standard brush length AT: 17.5 mm (0.69 in) MT: 12.3 mm (0.48 in)
Minimum brush length AT: 12.0 mm (0.47 in) MT: 7.0 mm (0.28 in)







3. Measure the brush spring force using a spring balance.
- If not within the minimum specification, replace the brush and brush holder component.

Standard spring force
AT: 23.3 - 31.7 N (2,38 - 3.23 kgf, 5.24 - 7.12 lbf)
MT: 18.3 - 24.9 N (1.87 - 2.53 kgf, 4.12-5.59 lbf)

Minimum spring force
AT: 10.0 N (1.02 kgf, 2.25 lbf)
MT: 5.9 N (0.6 kgf, 1.3 lbf)