Usage:
CONFIDENTIAL TIBU3677-00
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TECHNICAL INFORMATION BULLETIN |
AUGUST 28, 2002 |
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TRACK-TYPE TRACTOR |
D11R (7PZ) D11R CARRYDOZER (9XR, AAF) |
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Component Code(s) 5056 |
SUBJECT: CASE DRAIN RETURN SCREEN ON D11R AND D11R CARRYDOZER HYDRAULIC TANK MUST BE CHECKED
PROBLEM:
The drain lines from the fan pump case, implement pump case, fan motor case, and the EH pilot and RV valves return to the bottom of the hydraulic tank and pass through a return screen located inside the hydraulic tank. Debris can accumulate in the screen, blocking flow from the drain lines. This results in increased pressure, particularly in the pump and motor cases. High case drain pressures have been attributable to pump seal failures as well as overall pump failures. This has been most evident following a previous pump or motor failure.
SOLUTION:
The return screen should be removed and cleaned periodically, especially when one of the following has occurred:
- Implement or fan pump failure
- Fan motor failure
- Tank clean-out
- PCR (engine overhaul)
Illustration 1
Callouts:
Return screen (2) is easily accessible from the bottom of the tank. See Illustration 1. Use the following procedure to remove and clean screen (2):
- Drain the hydraulic tank and disconnect the drain lines. Refer to Steps 1, 2, 4, and 5 of Disassembly and Assembly, "Hydraulic Tank ? Remove."
- Unbolt block (4).
- Remove return screen (2) and clean screen with a clean, non-flammable solvent.
- Replace return screen (2).
- Replace block (4).
- Assemble drain lines. Refer to Steps 10 and 11 of Disassembly and Assembly, "Hydraulic Tank ? Install."
REFERENCES:
D11R (7PZ): Disassembly and Assembly, RENR2054, "Hydraulic Tank ? Remove and Install"
D11R Carrydozer (9XR, AAF): Disassembly and Assembly, SENR1796, "Hydraulic Tank ? Remove and Install"
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ALL RIGHTS RESERVED