Procedure to Troubleshoot All Refueling Pump Leaks on Certain Excavators{1295} Caterpillar

Excavator:

320C (S/N: BEA1-UP; EGA1-UP; GLA1-UP; ANB1-UP; MAB1-UP; PAB1-UP; AMC1-UP; BDC1-UP; BDE1-UP; DBG1-UP; GNG1-UP; JTG1-UP; AXK1-UP; BBL1-UP; EGL1-UP; JPL1-UP; BCN1-UP; SBN1-UP; BPR1-UP; HKT1-UP; RAW1-UP; BMZ1-UP)

320D (S/N: MDE1-UP; A8F1-UP; A9F1-UP; KGF1-UP; MGG1-UP; DHK1-UP; FAL1-UP; WBN1-UP; GDP1-UP; GKS1-UP; PCX1-UP; PHX1-UP; CXY1-UP; JGZ1-UP)

320E (S/N: DFG1-UP; TNJ1-UP; NAZ1-UP)

322C (S/N: BFK1-UP; BKM1-UP; BGR1-UP; EMR1-UP; MAR1-UP)

323D (S/N: RAC1-UP; SDC1-UP; WGC1-UP; CYD1-UP; SED1-UP; NDE1-UP; WNE1-UP; ZMF1-UP; CWG1-UP; JLG1-UP; LFL1-UP; BYM1-UP; PBM1-UP; NES1-UP; DKW1-UP)

323E (S/N: RAP1-UP; YRP1-UP; TDW1-UP)

324D (S/N: EJC1-UP; T2D1-UP; TRH1-UP; BTK1-UP; SYM1-UP; DFP1-UP; CJX1-UP)

324E (S/N: TLF1-UP; LDG1-UP; PNW1-UP)

325C (S/N: CRB1-UP; JLC1-UP; JLD1-UP; DTF1-UP; CSJ1-UP)

325D (S/N: GPB1-UP; PKE1-UP; KDG1-UP; LAL1-UP; MCL1-UP; GBR1-UP; SCR1-UP; T2S1-UP; CYW1-UP)

329D (S/N: MNB1-UP; XDB1-UP; BFC1-UP; DJF1-UP; EBM1-UP; SCY1-UP)

329E (S/N: RLD1-UP; TST1-UP; PLW1-UP)

330C (S/N: CYA1-UP; MCA1-UP; JAB1-UP; JCD1-UP; KDD1-UP; JNK1-UP; MKM1-UP; CAP1-UP; GKX1-UP; CGZ1-UP)

330D (S/N: GBC1-UP; NBD1-UP; GGE1-UP; B6H1-UP; EAH1-UP; THJ1-UP; FFK1-UP; LRM1-UP; ERN1-UP; JLP1-UP; RAS1-UP; MEY1-UP; T2Y1-UP)

336D (S/N: JBF1-UP; J2F1-UP; PRF1-UP; LMG1-UP; MYG1-UP; KDJ1-UP; ZML1-UP; PPN1-UP; MYP1-UP; JWR1-UP; DTS1-UP; KKT1-UP; M4T1-UP; WET1-UP)

336E (S/N: YCE1-UP; TMZ1-UP)

345B Series II (S/N: CCC1-UP; ALD1-UP; FEE1-UP; CDJ1-UP; DET1-UP; AKX1-UP)

345C (S/N: TBA1-UP; SPC1-UP; MTE1-UP; WDE1-UP; GPH1-UP; GCL1-UP; SCN1-UP; ELS1-UP; LYS1-UP; BWY1-UP)

345D (S/N: BYC1-UP; RAE1-UP; NEG1-UP; RGG1-UP; KFH1-UP; NLM1-UP; PBT1-UP; LKY1-UP)

349D (S/N: NNF1-UP; PZG1-UP; MEN1-UP)

349E (S/N: MZW1-UP; KFX1-UP)

365B (S/N: CTY1-UP; 9PZ1-UP)

365BL Series II (S/N: JMB1-UP; PEG1-UP; SDL1-UP)

365C (S/N: ELC1-UP; MEM1-UP; 0EM1-UP; PAR1-UP; MCY1-UP)

374D (S/N: PAS1-UP; PAX1-UP)

385B (S/N: FDL1-UP; CLS1-UP; BLY1-UP)

385C (S/N: MMA1-UP; KGB1-UP; KBC1-UP; SBE1-UP; T2E1-UP; T2F1-UP; KKK1-UP; EAM1-UP; WAW1-UP)

390D (S/N: WAG1-UP; WAP1-UP; KCZ1-UP)

Mobile Hydraulic Power Unit:

320C MHPU (S/N: MSN1-UP)

323D MHPU (S/N: DCJ1-UP; GRL1-UP; FAW1-UP; DCY1-UP; L5Z1-UP)

325D MHPU (S/N: SRC1-UP; C3N1-UP)

329D MHPU (S/N: L5G1-UP; L5H1-UP)

329E MHPU (S/N: K2L1-UP)

330C MHPU (S/N: MSD1-UP; MSL1-UP)

330D MHPU (S/N: D3D1-UP; GMN1-UP)

336D MHPU (S/N: L5K1-UP; M3M1-UP; M3N1-UP; M2P1-UP; M3S1-UP; JRX1-UP; NBZ1-UP)

336E MHPU (S/N: RBS1-UP; DSZ1-UP; T3Z1-UP)

345C MHPU (S/N: L5B1-UP; M3E1-UP; M3F1-UP; B6N1-UP)

345D MHPU (S/N: P5D1-UP; L5R1-UP)

349D MHPU (S/N: DKN1-UP)

349E MHPU (S/N: JAE1-UP; S3P1-UP)

365C MHPU (S/N: GSZ1-UP)

374D MHPU (S/N: JNZ1-UP)

385C MHPU (S/N: M4E1-UP; MSF1-UP; M3W1-UP)

390D MHPU (S/N: M1M1-UP)

Introduction

The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.

Problem

Presence of fuel in the tool box may occur due to the refueling system. Clean the interior of the tool box and the pump to improve leak detection accuracy.

When the tool box and refueling system is clean and dry, refuel the machine using the refueling pump with a minimum of half the tank capacity (to be drained if needed).

Solution

Note: During any disassembly or assembly, ensure that no debris enters the fuel circuit.

This procedure should be used to find out the common causes of leaks for the following:

• Fittings

• Foot valve

• Clamps

• Front cover

• Inner lip seal

Illustration 1	g03392096
(1) Foot valve (2) Pump harness terminal (3) Refueling pump (4) Clamps

Illustration 2	g03392098
(5) Fittings (6) Cover (7) Cover screws and lock washers

Illustration 3	g03392100
(8) O-ring

Illustration 4	g03392101
(9) Drain hole

Recommended Actions

Fittings

Specifically check the inlet and outlet fitting unions (5) for leakage.

The 229-1859 Refueling Pump and Motor Gp and the 368-5216 Fuel Transfer Pump Gp may develop leaks due to insufficient torque applied on fittings, fitting conformity, pump thread machining issue, or washer conformity.

Ensure that correct torque is applied on the 2 fittings by tightening the fittings to 128 N·m (94 lb ft). If a leak reoccurs, replace the appropriate parts using service kits.

Leaks may occur on the 165-4962 Refueling Pump and Motor Gp due to insufficient torque applied on fittings, fittings conformity, pump thread machining issue, or lack of sealant into the threads.

Replace the one 006-5707 Pipe Elbow and the two 229-1861 Hose Connectors . Before you assemble the parts, apply a sealant on the threads (Loctite 11415). Tighten both straight connectors to 80 N·m (59 lb ft) and the elbow by turning 1 1/2 turn after hand tight.

The 272-0709 Fuel Pump leaks may occur because of insufficient torque applied on fittings, fitting conformity, pump thread machining issues, or washer conformity.

Replace the elbow and the two fittings (5) that consists of two 301-2524 Hose Connectors and two 301-2527 Washer Seals . Tighten both fittings to 50 N·m (37 lb ft).

Foot Valve

Despite the check valve in the suction end of the line, some fuel may go out through that way. If a seepage or leak is noticed, the foot valve will have to be replaced.

Clamps

Three hose clamps (4) should be checked (foot valve, inlet, and outlet hose ends). The torque value of the clamps should be 7.5 N·m (66 lb in). The hose integrity should be verified nearby clamps. In case of doubts, disassemble the clamp and cut the hose 4 cm (1.57 inch) from the end and reassemble with a torque value of 7.5 ± 1 N·m (66 ± 9 lb in)

Front Cover

Remove the three screws (7). Disassemble the front cover (6) and check the O-ring seal (8) cleanliness. Then reassemble the cover and tighten the three screws to 7 ± 0.2 N·m (62 ± 2 lb in). Replace the appropriate parts using spare parts kits.

Inner Lip Seal

The inner lip seal may fail, causing a fuel leak from the pump head to the electrical part. The main symptoms are a leak through the hole under the pump (9) and/or a pump malfunction. In that case, the whole pump should be replaced.