1985/08/01 Caterpillar

All Caterpillar Engines Equipped With EG3P And EG10P Actuators And Used With Electric Governor Controls That Are Not Supplied By CTCo.

Woodward EG3P-EG10P Actuators are designed for use with the Woodward 2301 Governor. Actuators that have been used with other electrical governors have been replaced as defective and later found to have only minor calibration shifts.

The following engine problems can be the result of normal actuator wear that would not affect the operation of the 2301 Governor.

1. Engine will not start without manually moving actuator linkage.

2. Engine will not reach full load.

3. Parallel engines will not share load equally.

Before replacing the actuator, a simple diagnostic procedure should be followed.

1. Check linkage calibration. Refer to SENR2928-01, 2301 Electric Governors, System Operations, Troubleshooting, Service Procedures, Page 89, Procedure "E". Adjust and/or replace linkage to obtain the correct current reading ± 10 mA. Make sure that the engine will shut off at zero actuator current. Refer to the illustration.

Typical installation.

This procedure should correct most actuator related problems. If correct actuator current can be obtained and engine will shut off at zero actuator current, the actuator is not defective.

2. If problems persist such as speed stability or if an actuator problem is still suspected, for test only, replace the control system with a 2301 Governor. Refer to SENR2928-01, 2301 Electric Governor service manual for installation instructions. If the engine can then start, stop and otherwise perform properly. The original control system (governor) is at fault and should be replaced or repaired.

If a stability problem persists, refer to page 49 in the troubleshooting section of the service manual.

3. Load sharing problems between parallel engines are normally related to the control system and not to the actuator. Some controls depend upon precisely calibrated actuators to obtain load sharing. If an actuator calibration tighter than ± 10 mA is required to share load, it is not Caterpillar's responsibility to provide it.

Actuators that are returned for warranty will be inspected. Unless some other defect is identified, warranty will be denied if either of the following conditions are present.

1. The actuator is out of calibration and the lockwire on the cover is broken.

2. The actuator is in calibration.

Caterpillar can not guarantee that these actuators are compatible with any electric governor controls not supplied by Caterpillar.