1999/03/22 Caterpillar

777D (3PR, 2YW),
785C (1HW, 5AZ),
789B (7EK),
789C (2BW),
793B (1HL),
793C (4AR) Off-Highway Trucks;
776D (5ER),
784C (2PZ) Off-Highway Tractors;
854G (1JW) Wheel Tractors;
D11N (4HK),
D11R (8ZR, 9TR, 9XR) Tractors;
992G (7HR) Wheel Loaders;
5130 (7TJ, 5ZL),
5130B (4CS),
5230 (7LL) Excavators

Description of Change: New exhaust temperature sensor groups are used in the engine wiring groups on the 3500 EUI and 3500B engines in these machines. These new sensor groups have a longer [860 mm (34 in)]. lead length. The former sensor groups have a shorter [280 mm (11 in)] lead length. The longer lead length of the new sensor groups allows the sensor electronics to be mounted further from the hot exhaust manifold. This will improve the service life of the sensors. The new exhaust temperature sensor group for 3500B engines has a DT connector, while the new exhaust temperature sensor group for 3500 EUI engines has a HD connector.

Adaptable To: The new 163-7882 Exhaust Temperature Sensor Group replaces the 109-4367 Exhaust Temperature Sensor Group on 3500B engines in the above machines. The new 164-2441 Exhaust Temperature Sensor Group replaces the 3E-7826 Exhaust Temperature Sensor Group on 3500 EUI engines in the above machines. The chart lists the engine effectivity of the new exhaust temperature sensor groups.

Installation Procedure

1. Remove the former 109-4367 or 3E-7826 Exhaust Temperature Sensor from the exhaust manifold (A). Remove the 124-0289 Clip from the valve cover (B) that holds the sensor electronics. Save the clip and hardware. Unplug the sensor connector from the main wiring harness.

Location of new components for installing the new 163-7882 or 164-2441 Exhaust Temperature Sensor Group.

* 163-7872 or 165-2441 Exhaust Temperature Sensor Group (1).

* 4P-7581 Straight Clip or 4P-8134 "L" Clip (2).

* Previous location of 124-0289 Clip and location of new 4P-7581 Straight Clip or 4P-8134 "L" Clip (3).

* HD or DT connector (4).

* 124-0289 Clip (5).

* Exhaust temperature sensor group electronics (6).

* Exhaust Manifold (A).

* Valve Cover (B).

* Camshaft Cover (C).

2. Using a new 0X0509 Bolt and 5M-2894 Washer, install a 4P-7581 Straight Clip or 4P-8134 Clip ("L" Clip) in the position of the 124-0289 Clip that was removed from the valve cover in Step 1. (See Item 3 in the illustration.)

3. Lubricate the threads of the new 163-7882 or 164-2441 Exhaust Temperature Sensor Group (1) with 4C-5599 High Temperature Anti-Seize Compound before installation. Install the new exhaust temperature sensor in the exhaust manifold (A). Tighten the exhaust temperature sensor to a torque of 52.5 ± 5 N·m (39 ± 5 lb ft).

4. Secure the exhaust temperature sensor electronics (6) to the camshaft cover (C) using bolt, washer, and 124-0289 Clip (5) from Step 1.

5. Connect the new sensor connector (4) to the main wiring harness. Secure the exhaust sensor wiring to all clips using 9X-6772 Straps. 9X-6772 Straps should also be used to secure the main wiring harness and sensor connector.