Buhler 2335, 2425, 2290, 2375, 2360 manual Electronic Engine

SECTION 2 - OPERATION

The throttle lever, 1, in the cab of the tractor is attached to a potentiometer (POT) in the right hand side console. The POT sends an electronic signal (via the tractor wire harness) to the controller on the side of the engine, telling it where to set the engine speed. By moving the throttle lever, the POT signal is changed and the module reacts accordingly to set engine speed to match the lever position. During an engine speed derate (engine speed reduced by the engine control module to 1400 rpm), the module will not recognize or react to a throttle position above the 1400 rpm POT signal. If the throttle lever is moved above the 1400 rpm position, the engine will not speed up.

The engine control module controls the timing of and the amount of fuel that is injected into the engine via the electronic fuel injectors. This is called fuel metering and is the basis of power derate. Power derate will occur within a specified time span (e.g. low engine oil pressure) or will be gradual based on severity of the alarm condition present on the tractor (e.g. engine coolant temperature). The engine will now perform to a modified horsepower curve (20% less then maximum gross horsepower), with the end result being that it will no longer pull the same load at the same ground speed or at the same working depth. The tractor may have to be downshifted or the implement raised out of the ground to continue operation (or both).

The Cummins engine control module is also tied to three indicator lights on the warning light bar of the EICS. The Module controls illumination of these lights:

1.Engine Coolant Level

2.Yellow Engine Warning Light

3.Red Engine Warning Light

The EICS and Cummins control module combine to protect the engine from damage by informing the operator that a particular condition exists using the lights, performance derate or both lights and derate.

1

Figure 2-78

Electronic Engine

		Figure 2-79
1	2	3
		Figure 2-80

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