INSTRUMENT PANEL, INSTRUMENTS AND CONTROLS
The instruments ( Figure 1) generally required in the operation of a diesel engine consist of an oil pressure gage, a water
temperature gage, an ammeter and a mechanical tachometer. Also, closely related and usually installed in the general
vicinity of these instruments are certain controls consisting of an engine starter switch, an engine stop knob, an
emergency stop knob and, on certain applications, the engine hand throttle.
Torqmatic converters are equipped with an oil pressure gage and, in some instances, an oil temperature gage. These
instruments are mounted on a separate panel.
The oil pressure gage registers the pressure of the lubricating oil in the engine. As soon as the engine is started, the oil
pressure gage should start to register. If the oil pressure gage does not register at least the minimum pressure listed
under Running in the Engine Operating Instructions, the engine should be stopped and the cause of low oil pressure
determined and corrected before the engine is started again.
Water Temperature Gage
The engine coolant temperature is registered on the water temperature gage.
Figure 1. Typical Instrument Panel
An ammeter is incorporated into the electrical circuit to show the current flow to and from the battery. After starting the
engine, the ammeter should register a high charge rate at rated engine speed. This is the rate of charge received by the
battery to replenish the current used to start the engine. As the engine continues to operate, the ammeter should show a
decline in charge rate to the battery. The ammeter will not show zero charge rate since the regulator voltage is set
higher than the battery voltage. The small current registered prevents rapid brush wear in the battery-charging alternator.
If lights or other electrical equipment are connected into the circuit, the ammeter will show discharge when these items
are operating or the engine speed is reduced.
The tachometer is driven by the engine and registers the speed of the engine in revolutions per minute (rpm).
Engine Starting Motor Switch
The starting switch is mounted on the instrument panel with the contact button extending through the front face of the
panel. The switch is used to energize the starting motor. As soon as the engine starts, release the switch.
A stop knob is used on most applications to shut the engine down. When stopping an engine, the speed should be
reduced to idle and the engine allowed to operate at idle. for a few minutes to permit the coolant to reduce the
temperature of the engine's moving parts. Then the stop knob should be pulled and held until the engine stops. Pulling
on the stop knob manually places the injector racks in the "no-fuel" position. The stop knob should be returned to its
original position after the engine stops.
Emergency Stop Knob
In an emergency or if after pulling the stop knob, the engine continues to operate, the emergency stop knob