PRODUCT IMPROVEMENT PROGRAM FOR REWORKING THE BOOM LOWERING CHECK VALVES ON CERTAIN 374D AND 390D EXCAVATORS Caterpillar

PRODUCT IMPROVEMENT PROGRAM FOR REWORKING THE BOOM LOWERING CHECK VALVES ON CERTAIN 374D AND 390D EXCAVATORS

Usage:

REBE7661-02

Show/hide table

14Nov2011

(Revised 02Dec2011)

U-502

A-411

D-441

O-445

Show/hide table

*Safety*	PRODUCT IMPROVEMENT PROGRAM FOR REWORKING THE BOOM LOWERING CHECK VALVES ON CERTAIN 374D AND 390D EXCAVATORS
5456 5057		PI10877

Show/hide table

NOTE:

This Program must be administered as soon as possible. When reporting the repair, use "PI10877" as the Part Number and "7751" as the Group Number, "56" as the Warranty Claim Description Code and "T" as the SIMS Description Code.
Exception: If the repair is done after failure, use "PI10877" as the Part Number, "7751" as the Group Number, "96" as the Warranty Claim Description Code, and "Z" as the SIMS Description Code.

Show/hide table


NOTE:	This Revised Service Letter replaces the 18Nov2011 Service Letter. Changes have been made to Parts Needed and Affected Product.

Show/hide table

PROBLEM

Show/hide table

The boom lowering check valves need to be reworked on certain 374D and 390D Excavators. The actual boom lowering check valves could have an internal poppet failure, which could result in failure of the boom lowering check valve so that it would not properly function when required to control the boom lowering speed, with the potential for serious injury or death to a ground person.

AFFECTED PRODUCT

Show/hide table

Model	Identification Number
374D L	PAP00143, 159 PAS00159, 184, 515, 517 PAX00112-00114, 116-122, 124-126, 128, 130-132, 134, 136-137, 139-152, 155-158, 160-162, 164, 301, 306-308, 313, 316-334, 337, 339-344
374D OEM	JNZ00109, 113-114
390D L	WAG00131-00135, 137-145, 147-149, 151-153, 158-170, 173-175 WAP00184, 224, 250 WBT00170, 172, 189

PARTS NEEDED

Show/hide table

Qty	Part Number	Description
2	3K0360	SEAL-O-RING (Before Failure Only)
2	6V8397	SEAL-O-RING-ORFS (Before Failure Only)
8	8T3957	BOLT-SOCKET HEAD (Before Failure Only)
2	0951599	SEAL-O-RING (Before Failure Only)
2	0951793	RING-BACK UP (Before Failure Only)
2	1093656	ELBOW-90 DEG (Before Failure Only)
2	3698570	SEAT (Before Failure Only)
2	3698571	VALVE-CHECK (Before Failure Only)
2	3698572	SPRING-CHK VALVE (Before Failure Only)
2	3698573	COVER (Before Failure Only)
In order to allow equitable parts availability to all participating dealers, please limit your initial parts order to not exceed 45% of dealership population. This is an initial order recommendation only, and the ultimate responsibility for ordering the total number of parts needed to satisfy the program lies with the dealer.

ACTION REQUIRED

Show/hide table

Refer to the attached Rework Procedure.

Show/hide table

OWNER NOTIFICATION

Show/hide table

U.S. and Canadian owners will receive the attached Owner Notification.

SERVICE CLAIM ALLOWANCES

Show/hide table

Caterpillar		Dealer Suggested		Customer Suggested
Parts %	Labor Hrs%	Parts %	Labor Hrs%	Parts %	Labor Hrs%
100%	100%	0%	0%	0%	0%

Show/hide table

NOTE: This is a 4.0-hour job

Show/hide table

PARTS DISPOSITION

Show/hide table

Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.

MAKE EVERY EFFORT TO COMPLETE THIS PROGRAM AS SOON AS POSSIBLE.

Show/hide table

COPY OF OWNER NOTIFICATION FOR U.S. AND CANADIAN OWNERS

XYZ Corporation
3240 Arrow Drive
Anywhere, YZ 99999

SAFETY - PRODUCT IMPROVEMENT PROGRAM FOR REWORKING THE BOOM LOWERING CHECK VALVES ON CERTAIN EXCAVATORS

MODELS INVOLVED - 374D and 390D Excavators

Dear Caterpillar Product Owner:

The boom lowering check valves need to be reworked on the products listed below. The actual boom lowering check valves could have an internal poppet failure, which could result in failure of the boom lowering check valve so that it would not properly function when required to control the boom lowering speed, with the potential for serious injury or death to a ground person. You will not be charged for the service performed.

Contact your local Caterpillar dealer immediately to schedule this service. The dealer will advise you of the time required to complete this service.

Please refer the dealer to their Service Letter dated 14Nov2011 when scheduling this service.

We regret the inconvenience this may cause you, but urge you to have this service performed for your added safety and satisfaction.

Caterpillar Inc.

Identification #(s)

Attached to 14Nov2011 Service Letter

Rework Procedure

Show/hide table

1. Caution: Park the machine on a level surface. Ensure that all work tools are in the recommended servicing position before reworking the machine. Relieve the pressure on the boom cylinder line before removal of the boom lowering check valves.

Refer to KENR6406, Disassembly and Assembly, for 374D Excavators.

Refer to KENR6408, Disassembly and Assembly, for 390D Excavators.

Identify the hydraulics hose connections, before removal, by making a mark. Disconnect all hydraulic lines from the boom lowering check valves. Plug all hydraulic lines in order to reduce oil spillage and risk of contamination. Remove both boom lowering check valves from the machine.

2. Refer to Image1.2.1 and 1.2.2 for the location of the boom lowering check valves.

Image1.2.1

Image1.2.2

3. Refer to Image1.3.1 for parts identification.

Remove bolts (6) from cover (7), from both boom lowering check valves. Insert a screw in seat (3) and pull it out. Valve (1) and spring (2) will come out. Refer to Image1.3.2. Discard seat (3), valve (1), spring (2), O-ring (4), and back up ring (5), they will not be reused.

Image1.3.1

Image1.3.2

4. Refer to Image1.4.1 for parts identification.

(1) 369-8571 Boom Lowering Check Valve
(2) 369-8572 Spring
(3) 369-8570 Seat
(4) 095-1599 O-Ring Seal
(5) 095-1793 Back Up Ring
(6) 8T-3957 Bolt
(7) 369-8573 Cover

Prepare new seat (3) with new O-ring (4), and new back up ring (5). Pay close attention to the correct direction, in order to avoid a leak.

Install new valve (1) and new spring (2) into the boom lowering check valves.
Insert new seat (3) and install new cover (7). Install bolts (6). Tighten the bolts (6) to 100 +/- 20 N.m.

Parts are common for 374D and 390D Excavators.

Image1.4.1

Image1.4.2

5. After the new parts are in place, install both of the boom lowering check valves to the machine. Re-connect the hydraulic hoses, note the identification marks that were done before the disassembly. Do not connect the balancing lines yet. Refer to Image1.5.1 and 1.5.2.

Image1.5.1

Image1.5.2

For the tightening torques, refer to Image1.6.1 and 1.6.2. The 374D is shown in Image1.6.1 and 1.6.2, the same tightening torque is required for the 390D.

(A) 100 +/- 20 N.m
(B) 48 + 5/- 0 N.m
(C) 48 + 5/- 0 N.m
(D) 100 +/- 20 N.m
(E) 190 + 19/- 0 N.m
(F) 100 +/- 20 N.m

Image1.6.1

Image1.6.2

6. For the balancing lines, change the orifice connector on the port. Refer to Image1.7.1 and 1.7.2.

Original Parts:
(G) 148-8367 Adapter Assembly
(H) 307-4849 Connector Assembly

New Parts:
(J) 109-3656 Elbow
(K) 3K-0360 O-Ring Seal
(L) 6V-8397 O-Ring Seal

Tightening Torque:
(M) Boom Lowering Check Valve Side - 48 + 5/- 0 N.m
(N) Hose Side - 43 + 5/- 0 N.m

Parts are common for 374D and 390D Excavators.

Image1.7.1

Image1.7.2

7. In case the the boom lowering relief valves need to be adjusted, please refer to KENR7775, Testing and Adjusting", for the 374D and the KENR7735, Testing and Adjusting, for the 390D.