Tronair 02A7843-0112, Operation & Service Manual

Page: 5 / 60

Model: 02A7843-0112
25 Ton Single Stage Jack
01/2004 | Rev. 04 Page | 2
6.0 MAINTENANCE
GENERAL

All maintenance and/or repair work should be done using good workmanship practices and proper tools.

The work area should be clean and free of dirt.

When O-rings and backup rings are removed, every effort should be made to avoid the contact of tools with the critical
surfaces of parts. Surface deformities could cause degradation of seals and failure.

It is good practice to replace both O-rings and back-up rings once removed. Cut and damaged O-rings normally result in
fluid leakage.

If cylinder bore is found to be rusty, it may be honed to a maximum diameter of 4.506 inches and a surface finish of 16
micro inches. If pitting in the bore cannot be removed by this process, the jack cylinder must be replaced before the jack
can be returned to service.

At this time, flush old hydraulic fluid and dirt from overall system and replenish with new, clean hydraulic fluid.
6.1
SERVICING JACK
To Disassemble Jack:
1. Remove mounting plate (Item 43) by unscrewing five (5) socket head cap screws (Item 42).
2. Raise ram assembly (Item 45) to the point where it can be lifted from the jack cylinder.
To Re-assemble Jack:
1. Re-assemble in reverse order of above. Torque five (5) socket head cap screws (Item 42) to 100 ft-lbs.
NOTE: To minimize air entrapment under the ram, raise the oil level in the cylinder to chamfer of the cylinder prior to
ram insertion.
6.2
REMOVING AND SERVICING PUMP
NOTE: If pump is found faulty, call the factory for replacement or replace seals as follows:
1. Review Appendix I - HC-1751 Hand Pump Parts List and Illustrations.
2. Clamp suction (push on) hose and remove hose from pump.
3. Uncouple fitting of hydraulic hose from pump.
4. Remove pump from jack.
5. Remove cotter pin from clevis pin.
6. Remove four (4) socket head cap screws.
7. Remove flanges.
8. Remove tube assembly.
9. Replace O-rings and backup ring. (See Appendix I for kits available).
10. Re-assemble in reverse order.
6.3
JACK FUNCTION LOAD TEST
NOTE: If function load testing is required:
1. Take all necessary precautions to prevent injury.
2. Always jack against a load and never against the jack itself.
3. Do not exceed a test load equal to the jack rated capacity plus 10%.
6.4
PNEUMATIC PUMP
See Appendix II - Haskel MLP-20/46D Pump information and Haskel Drawing 28550 for complete parts list and repair
information.