37-MT, 41-MT, and 42-MT Series Starting Motors Caterpillar

Disassemble the Starting Motor

Note: The disassembly and assembly that follows is of the 24 volt starting motor. The 12 volt is similar.

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Illustration 1	g00810559

1. Disconnect wire assembly (4) from solenoid (1). Disconnect motor terminal connector (3) from the starting motor housing.

2. Remove three bolts (2) from the shift lever housing. Do not disassemble the solenoid. The parts inside the solenoid are not serviceable.

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Illustration 2	g00818016

3. Remove the O-ring seal and bushing (5) .

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Illustration 3	g00810580

4. Remove the nut (6). Remove the solenoid from the shift lever housing.

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Illustration 4	g00810574

5. Remove the negative terminal nuts "-", wire assembly (2), and washers. Remove six bolts (8) and rear housing (7) .

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Illustration 5	g00818558

6. If necessary, remove bushing (9) from the rear housing.

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Illustration 6	g00810576

7. Remove washer (12) from the armature shaft. Lift brush springs (10) and pull the brushes away from the commutator. Position the brush springs (10) on the side of the brushes in order to hold the brushes in the holders.

8. Disconnect field winding leads (13) from brush holder (11). Remove the brush holder.

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Illustration 7	g00818538

9. Remove brushes (15) and negative "-" terminal (14) from the brush holders.

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Illustration 8	g00810579

10. Scribe a line on the pinion drive, the shift lever and the starting motor housings for the correct alignment at assembly.

11. Remove six bolts (17) and pinion drive housing (16) .

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Illustration 9	g00810582

12. Remove retainer (18) with tool (A). Remove shift lever pin (20). If necessary, remove the O-ring seals from the shift lever pin.

13. Remove pinion drive (19) and the shift lever.

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Illustration 10	g00810585

14. Remove the brake disc from the armature shaft. Remove five bolts (22), shift lever housing (21) and the washer. If necessary, remove the outside O-ring seals.

15. If necessary, remove the seal and the bushing from the shift lever housing.

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Illustration 11	g00810588

16. Remove armature (22) from the starting motor housing.

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Illustration 12	g00810589

17. Remove the following components from the starting motor housing: eight screws (26), pole shoes (25) and field winding coil (24). It may be necessary to use an impact driver to remove screws (26) .

18. Clean the armature, field winding coil and pinion drive with mineral spirits and a brush.

    Note: If the commutator is dirty, the commutator may be cleaned with Number 00 sandpaper. Do not use emery cloth.

19. Inspect all parts for wear and damage.