Installation of the 254-4334 Check Valve Kit on the 228-5896 Unit Injector Hydraulic Pump Gp and the 228-5898 Unit Injector Hydraulic Pump Gp {1714} Caterpillar

On-highway Engines:

C7 (S/N: KAL1-UP)

C9 (S/N: MTB1-UP; 9DG1-UP)

Marine Engines:

C-9 (S/N: CSN1-UP)

Introduction

This Special Instruction provides the rework procedure for the installation of the 254-4334 Check Valve Kit on the 228-5896 Unit Injector Hydraulic Pump Gp and the 228-5898 Unit Injector Hydraulic Pump Gp . The parts kit includes a temporary service bolt that is used during the removal of the fuel transfer pump in order to prevent the body of the unit injector hydraulic pump from separating. Once the fuel transfer pump has been reinstalled onto the HEUI pump, the service bolt is then removed.

Removal of the HEUI Pump

Prior to removing the HEUI pump, wash the engine in order to remove all of the dirt from the area that surrounds the HEUI pump. Remove the HEUI pump. Refer to Disassembly and Assembly, "Unit Injector Hydraulic Pump - Remove" for the correct procedure.

Note: Do not allow any debris to enter the HEUI pump or the HEUI pump parts. Allowing debris to enter the HEUI pump will cause pump failure.

Note: Do not attempt to perform this rework procedure while the HEUI pump is still on the engine.

Removing the Fuel Transfer Pump from the HEUI Pump

1. Use a vise (3) in order to secure the HEUI pump (1) vertically with the drive gear (4) on the bottom. Make sure that the vise has jaws that are made from aluminum or some other soft material. Do not clamp on the gear or the front mounting flange. Do not rest the pump with the drive gear (4). Refer to Illustration 1.

   Note: If any debris remains on the pump, plug all of the ports on the pump and spray the external parts of the pump with an appropriate cleaner.

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Illustration 1	g01077607
(1) HEUI pump (2) Fuel transfer pump (3) Vise (4) Drive gear

2. Remove the single tie bolt (6) that is located in the top left corner of the pump by using Tooling (C). Refer to Illustration 2. Only remove the single tie bolt (6). Removing more bolts will result in damage to the pump.

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Illustration 2	g01077637
(1) HEUI pump (2) Fuel transfer pump (4) Drive gear (5) Seal (6) Tie Bolt (7) Bolts for the fuel transfer pump (8) Tie Bolts (9) Location for service bolt

3. Replace tie bolt (6) with the temporary service bolt (9) that is provided in the service kit.

   Note: The service bolt that is provided in the kit has an undersized bolt head. The service bolt prevents the body of the HEUI pump from separating during service. Do not remove the service bolt until the fuel transfer pump has been completely reinstalled.

4. Tighten the service bolt (9) to 10 N·m (7.4 lb ft) by using Tooling (D) .

   Note: Do not place an excessive torque on the service bolt. The aluminum housing of the pump could be damaged.

5. After installing the service bolt (9) in the top left location, remove the three bolts (7) that fasten the fuel transfer pump to the HEUI pump by using Tooling (B) .

6. Proceed by removing the remaining three tie bolts (8) by using Tooling (C) .

7. Separate the fuel transfer pump from the HEUI pump. Refer to Illustration 3.

Illustration 3	g01077676
(1) HEUI pump (2) Fuel transfer pump (9) Service bolt (10) Seals (11) Seal (12) Check valve assemblies (Qty 7)

Removing the Check Valve Assemblies from the HEUI Pump

1. Remove the two high pressure seals (10). Discard the two seals. Refer to Illustration 3.

   Note: Take caution in order to avoid wiping any debris into the pump.

2. Remove the seal (11) from the bearing on the fuel transfer pump. Discard the seal. Refer to Illustration 3.

3. Remove the seven check valve assemblies (12) from the HEUI pump by using Tooling (A). Refer to Illustration 3.

   Note: Take caution in order to avoid wiping any debris into the pump.

4. Inspect all check valve assemblies (12) for broken springs by using the following procedure.

   1. Place the flat end of the check valve on a work bench so that the valve is positioned vertically.

   2. Press on the check valve poppet (13) with a small cross tip screwdriver and then release the check valve poppet. There should be some resistance from the spring in the check valve. The poppet should return to the initial position after releasing. Refer to Illustration 4.

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Illustration 4	g01077708
(12) Check valve assembly (13) Check valve poppet

5. If any of the valve springs are broken, do not advance. Stop the rework procedure. Replace the HEUI pump.

6. If none of the valve springs are broken, proceed to the next section.

Installing Check Valve Assemblies into the HEUI Pump

1. Install seven new 254-4302 Check Valve Assemblies (12) that are found in the 254-4334 Check Valve Kit .

2. Insert the check valve assemblies by hand and press on the back of the valve until the valve is fully seated in the barrel.

3. Tighten each valve to 9.0 ± 1.5 N·m (80 ± 13 lb in) by using an appropriate torque wrench and Tooling (A) .

   Note: The check valve assemblies must be torqued to the correct specifications. Failing to apply the correct torque could result in loosening of the valve or cracking of the valve in the field.

4. In order to ensure that all valves are torqued, repeat Step 3.

Installing the Fuel Transfer Pump onto the HEUI Pump

1. Install the two new 239-2402 Seals (10) on the back face of the HEUI pump (1). Refer to Illustration 5.

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Illustration 5	g01077898
(1) HEUI pump (10) 239-2402 Seals

2. Install a new 179-8128 Seal (11) on the fuel transfer pump (2). Refer to Illustration 6. Use 1U-6396 O-Ring Assembly Compound in order to hold the seal in place during assembly. Ensure that the seal is completely seated.

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Illustration 6	g01077908
(2) Fuel transfer pump (11) 179-8128 Seal

3. Do not remove the service bolt. Position the fuel transfer pump on the HEUI pump. Be sure to properly align the drive tang on the fuel transfer pump with the drive slot on the HEUI pump.

   Note: Failure to align the drive tang prior to the installation of the fuel transfer pump will not allow proper assembly of the two pumps.

4. Install the three mounting bolts (7) for the fuel transfer pump (2). Tighten the bolts to a torque of 4.0 ± 0.2 N·m (35 ± 1.5 lb in)by using Tooling (B). Do not remove the service bolt (9) . Refer to Illustration 7.

5. Install the three tie bolts (8). Tighten the bolts to a snug fit by using Tooling (C). Refer to Illustration 7.

6. Remove the service bolt (9) that is located in the upper left hole by using Tooling (D). Install the remaining tie bolt (6) and tighten the tie bolt to a snug fit by using Tooling (C). Refer to Illustration 7.

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Illustration 7	g01077637
(1) HEUI pump (2) Fuel transfer pump (4) Drive gear (5) Seal (6) Tie Bolt (7) Bolts for the fuel transfer pump (8) Tie Bolts

7. Tighten bolts 1 through 4 in a numerical sequence to a torque of 28 ± 5 N·m (21 ± 4 lb ft) by using Tooling (C). Refer to Illustration 8.

8. Tighten bolts 5 through 7 in a numerical sequence to a torque of 8.0 ± 0.4 N·m (70 ± 3.5 lb in) by using Tooling (B). Refer to Illustration 8.

9. In order to ensure that the gasket completely compresses, repeat Step 7 through Step 8.

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Illustration 8	g01077932
Tightening sequence for installing the fuel transfer pump

10. Stamp the back of the HEUI pump with rework code "CV". Also stamp the left side of the HEUI pump with rework code "CV". Refer to Illustration 9.

    Note: The identifier must be visible on the engine for future identification.

Illustration 9	g01079265
(14) Location for stamping the rework code onto the HEUI pump

Reinstalling the HEUI Pump

Install the HEUI pump on the engine. Refer to the Disassembly and Assembly Manual for the correct procedure. Ensure that the system does not have any leaks.

Note: A new 227-5904 O-Ring Seal (5) is provided in the 254-4334 Check Valve Kit . Discard the old seal and install the new seal on the HEUI pump.