Caterpillar Electronic Locomotive Control System II Caterpillar

There are three locations for the rack position sensor, one for each type of engine (3412, 3500 and 3600). The 3500 and 3600 Engines share a common assembly group for the sensor housing (7W7373).

3500 Rack Position Sensor

The rack sensor is installed on the front drive housing on the side opposite the rack actuator. The rack sensor module consists of three parts:

a. Threaded Guide

b. Push Rod

c. Sensor Assembly

RACK SENSOR INSTALLED ON LEFT SIDE OF ENGINE
(1) COVER. (2) RACK SENSOR.

A rack stop lever must be installed on the same side as the rack sensor.

1. Remove cover (1) from the front of the front drive housing on the same side that rack sensor (2) will be installed.

2. Install rack stop lever (3) with two bolts to fuel control linkage (4).

3. Install cover (1).

INSTALLING RACK STOP LEVER
(3) RACK STOP LEVER.

FRONT DRIVE HOUSING
(4) FUEL CONTROL LINKAGE.

4. Install threaded guide (5) into the front drive housing of the engine on the same side the rack stop lever was installed.

5. Install the clip on pushrod (6) and install pushrod in threaded guide.

THREADED GUIDE AND PUSHROD INSTALLED
(5) THREADED GUIDE. (6) PUSHROD.

6. Install rack sensor (2) over threaded guide and pushrod.

7. Connect the wires from rack sensor (2) to the engine wiring harness.

NOTE: The rack sensor must be calibrated on the engine before the system is run.

3600 Rack Position Sensor

Rack Position Sensor Installed
(1) Rack Position Sensor. (2) Fuel Injection Control Housing.

The rack position sensor is installed on the fuel injection control housing located on the right side of the rear housing. The rack position sensor module consists of four parts:

a. Threaded Guide

b. Push Rod

c. Sensor Assembly

d. Lever

Rack Position Sensor
(1) Rack position sensor. (2) Fuel injection control housing. (3) Ring. (4) Threaded guide. (5) Pushrod. (6) Cover assembly. (7) Bracket. (8) Shaft. (9) Lever.

1. Put lever (9) in position on shaft (8) and install the bolt that holds it in place.

2. Install bracket (7) on the fuel injection control housing.

3. Install threaded guide (4) in bracket (7).

4. Install ring (3) on pushrod (5), and install the pushrod in the threaded guide.

5. Put rack position sensor (1) in position over the pushrod and threaded guide and install the bolts that hold it to bracket (7).

6. Connect the wires from rack position sensor (1) to the engine wiring harness.

7. Install cover assembly (6).

NOTE: The rack position sensor must be calibrated on the engine before the system is run.