621H, 623H and 627H Wheel Tractor-Scrapers Power Train Caterpillar

Disassembly Procedure

Start By:

1. Remove the transmission hydraulic control valve.

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Illustration 1	g02669678

1. Remove all hose assemblies (1) .

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Illustration 2	g02669736

2. Remove bolts (2) and relief valve (3) .

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Illustration 3	g02669798

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Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

3. Remove bolts (4) and cover (5) . Remove bolts (6) and cover (8) . Remove adjusting screw (7) from cover (8) .

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Illustration 4	g02670398

4. Remove piston (10) , spring (11) , spool assembly (12) , and slug (13) .

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Illustration 5	g02670436

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Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

5. Remove retaining ring (14) , retainer (15) , spring (16) , and ball (17) .

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Illustration 6	g02670876

6. Remove relief valve (18) .

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Illustration 7	g02670877

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Personal injury can result from being struck by parts propelled by a released spring force. Make sure to wear all necessary protective equipment. Follow the recommended procedure and use all recommended tooling to release the spring force.

7. Remove cap (24) , spring (23) , spacers (22) , relief valve (21) , and seal (19) from body (20) .

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Illustration 8	g02670918

8. Remove bolts (25) , modulating valve (26) , and plate (27) .

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Illustration 9	g02670956

9. Remove nut (28) , washer (29) , coil assembly (30) , and connector (31) from valve assembly (32) .

10. Repeat Steps 8 and 9 for the remaining modulating valves.