Usage:
All Track-Type Equipment
Reference: Special Instruction, Forms SEHS8513 and SEHS8667 on track repair procedures for D10 and D11N Tractors, respectively, and Special Instruction SMHS8557 on use of the portable 8T3115 Track Lubricator Group.
Reference: Service Magazine, September 1, 1986, Page 3, "Inspection And Replacement Of Parts In Portable Track Repair Groups".
Track repairs are necessary when a dry track joint, a broken link, or failed master link occurs. Job site repairs are performed under adverse conditions. The easiest access to the track joints and job safety are the most important things to consider for job site repairs. Other considerations are the techniques to be used, location of the joint, and the serviceman's preference.
Track joint repairs are a necessary part of providing users with timely service. Track life will be extended and downtime will be reduced. Prompt, quality repairs will greatly contribute to total undercarriage service. All personnel involved with track repairs should review the following hints in order to promote successful job site repairs.
1. Check the condition of the track repair tooling. See referenced Service Magazine article. Examine these tools for abnormal wear or damage each time they are used. Regardless of how the tools are made or what material is used, continued use will cause wear.
2. Give some considerations as to where to position the joints that need repaired. As a serviceman, you may already have preferences, but consider the following:
... Repairs made over the front roller frame require additional blocking to prevent track sag, additional climbing on and off the machine, and cause difficulty in viewing the operation.
... Repairs at the rear of the machine offer minimum blocking, ease of sight, one hoist to hold the press support, and ground level work.
... The track can be separated at the master joint, allowing repair off the machine and on the ground. Minimum blocking is required, repair is performed at ground level, and the view of the work is best in this location.
3. For assembly of the track.
... Always replace the seals and thrust rings and inspect the adjacent links.
... Avoid seal damage when the joints are put back together. A nick or cut can cause loss of track oil and the need for a future repair and more machine downtime.
... Keep the joint areas clean.
... Prior to assembly, inspect the link pin bores for broaching. Correct alignment of the press with the pin bore will keep broaching to a minimum, ensure safe operation, and result in quality repairs.
... Keep the track repair tools level. Use the correct tooling. Keep the ram face clean, smooth and closely centered.
... It is recommended that a replacement joint be assembled ahead of time in your shop for each joint to be repaired. This saves time and improves the quality of repair.
4. During disassembly and assembly, the adjacent link assembly must be spread slightly to clear the bushing projection and to prevent seal damage. When the link assembly is spread, use care to avoid link movement on the bushings. If the link moves on the bushing, the bushing protrusion will not be correct and there may be cheek-to-cheek interference.
5. Check end clearance. End clearance is the amount of sideways movement between two links. Zero end clearance is best. Be sure the bushing projection is correct. Check for correct operating pressure of the press. Zero end clearance may not be obtained if the pressure is too low.
6. After reassembly, the joint is ready for lubrication. Use the portable 8T3115 Track Lubricator Group. Before the joint is filled, evacuate the joint for 10 to 15 seconds. There should be no reduction in vacuum. Next, fill the joint with SAE 80W-90 Extreme Pressure Gear Oil until the needle on the gauge stabilizes. Fill time will vary. Repeat the oil fill procedure until no pressure drop is noticed. The referenced Special Instruction covers this procedure.
7. Track shoe bolt torque and the correct tightening tools vary considerably from machine to machine. For example, track bolts on the D11N Tractor require a pretorque of 1500 ± 70 N·m (1100 ± 50 ft lb). This high torque, plus the additional turn method, requires the 8T9130 Hydraulic Track Wrench Assembly. On other machines, the 6V6080 or 5P3508 Torque Multiplier, or the 6V200 Hydraulic Wrench can be used to obtain the correct final torque.