Product Support Program For Replacing Cracked Jumper Tubes And Replacing The Fuel Return Elbow At The Rear Of The Cylinder Head On Certain 3116 And 3126 HEUI Engines Caterpillar

NOTE: The information supplied in this service letter may not be valid after the termination date of this program. Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.

NOTE: This Program can be administered either before or after a failure. In either case the decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS8826" as the Part Number and "7755" as the Group Number. If administered before failure, use "56" as the Warranty Claim Description Code and use "T" as the SIMS Description Code. If administered after failure, use "96" as the Warranty Claim Description Code and use "Z" as the SIMS Description Code.

NOTE: This Revised Service Letter replaces the March 4, 1997 (Revised June 1997) Service Letter. Changes have been made to the Termination Date.

Termination Date

Problem

Certain 3116 and 3126 HEUI Engines that have 1249714 or 1136110 Jumper Tubes may crack on the injector side. If a crack occurs the engine can be shut down due to an oil leak in the high pressure system. Warning signals are: multiple 164-11 events, hard hot starting, low power, and/or an inability of the hydraulic oil pressure to maintain the desired level- (actual does not equal desired).

Certain 3116 and 3126 Engines could also experience fuel filter seal leaks. This can result from debris blocking the internal orifice in the fuel return line at the rear of the cylinder head.

Affected Product
Model & Identification Number

Group 1

3116 (8WL1-1098)

3126 (1WM1-6706 4ES1-276 3TR1-218 )

Group 2

3116 (8WL1-1059)

3126 (1WM1-6270 4ES1-273 3TR1-207 )

Parts Needed

Group 1

6 - 9M1974 Washer

6 - 1077808 Washer

6 - 1136091 Seat

6 - 1136303 Seal

1 - 1192940 Gasket

6 - 1355980 Tube Assembly

6 - 1355973 Clamp

NOTE: The 1355973 Clamp is required only on 1WM1-2158 Engines which may still be equipped with the 1077799 Clamp. The 1077799 Clamps can be identified by the raised number which can be viewed with the valve cover off.

Group 2

1 - 1R0759 Fuel Filter

1 - 1333736 Elbow Assembly

Action Required

Parts Stock

Remove all 1136145 Tapered Seats, 1136110 and 1249714 Tube Assemblies and 1077799 Clamps from parts stock.

Affected Product

See the attached rework procedure.

Service Claim Allowances

Group 1

Parts Stock

Submit one claim for all 1136145 Tapered Seats, 1136110 and 1249714 Jumper Tubes, and 1077799 Clamps removed from parts stock.

Affected Product

NOTE: An additional 1.6 hours should be added using SMCS Code 1714-500 if the rework is performed in a motor home, cab type (RV).

Group 2

Affected Product

Parts Disposition

TEPS/MEPS Dealers must return the affected part(s) to their Caterpillar dealer.

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

Attach.

(1-Rework Procedure)

Rework Procedure

Cracked Jumper Tubes

1. Remove the 1136145 Tapered Seat and install a 1136091 Spherical Seat.

2. Use a new 1355980 Tube. Scrap the used tube and the 1136145 Tapered Seat.

3. Place a 1077808 and 9M1974 Clamp Washer beneath the 8T0292 Bolt, insuring the 9M1974 Washer is on top of the 1077808 Washer.

4. Position the 1136091 Seat on the center of the injector top.

5. Install the 1355980 Tube Assembly into the manifold end first, then the injector end. Start the flare nut into the manifold and tighten by hand until the flare is seated on the tuned fitting, making sure that the tube is centered in the flare nut.

6. Install two 1253296 #10 Socket Head Screws at the injector end of the tube. Tighten evenly until hand tight, assuring that the tube is centered in the flange.

7. Install the 1355973 Clamp, 9M1974 Washer and 1077808 Washer. Tighten the 8T0292 Bolt to a torque of 30 ± 4 N·m (22 ± 3 lb ft), and the tube should be entered in the clamp.

NOTE: The injector must bottom in the brass sleeve bore with the tube flange parallel to the injector top surface.

8. Tighten the flare nut at the manifold to a torque of 40 ± 5 N·m (30 ± 4 lb ft).Loosen the nut and then tighten again to a torque of 40 ± 5 N·m (30 ± 4 lb ft).

9. Tighten each #10 Socket Head Screw to 3 ± 1 N·m (27 ± 9 lb in) then tighten each #10 Socket Head Screw to 5 ± 1 N·m (45 ± 9 lb in).

10. Tighten each 8T0292 M8 Bolt to a torque of 30 ± 4 N·m (22 ± 3 lb ft).

11. After the rework has been completed, stamp the engine block with the letters "SS".

NOTE: The letters should be stamped on the machined surface on the block just to the rear of the rear-most side cover.

Motor coaches are installed with the engine facing rear.

Fuel Filter Seal Leakage

1. Remove the fuel return line (Y) from the 1243545 Valve Housing (2) at the rear of the cylinder head (reference Illustration 1). Check to be sure the .50 mm (.020 inch) orifice (X) in the end of the valve housing is not plugged.

2. Replace the 8T0788 Elbow (1) with a new 1333736 Elbow Assembly. The new elbow assembly includes a stainless steel mesh filter screen to help prevent foreign material or debris from plugging the orifice in the valve housing.

3. Install a new fuel filter, 1R0759 Filter Assembly. The 1R0759 Filter Assembly is qualified to a higher fuel system pressure, while providing equivalent filtration levels.

NOTE: Be sure to tighten the fuel filter ONE FULL TURN after the fuel filter seal contacts the filter base for maximum sealing capability.

4. After the rework has been completed, stamp the engine block with the letters "SE".

Location of components in typical fuel filter lines group. 0.50 mm (0.20 inch) Orifice (X) in end of the valve housing. Fuel return line (Y), 8T0788 Elbow (1) 1243545 Valve Housing (2)

Illustration 1.

Illustration 2