DETROIT DIESEL
SECTION 4
ENGINE EQUIPMENT
INSTRUMENT PANEL, INSTRUMENTS AND CONTROLS
The instruments (Fig. 1) generally required in the
operation of a diesel engine consist of an oil pressure
gage, a water temperature gage, an ammeter and a
An ammeter is incorporated into the electrical circuit
mechanical tachometer. Also, closely related and
to show the current flow to and from the battery. After
usually installed in the general vicinity of these
starting the engine, the ammeter should register a high
instruments are certain controls consisting of an
charge rate at rated engine speed. This is the rate of
engine starter switch, an engine stop knob, an
charge received by the battery to replenish the current
emergency stop knob and, on certain applications, the
used to start the engine. As the engine continues to
engine hand throttle.
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
Torqmatic converters a r e equipped with an oil
than the battery voltage. The small current registered
pressure gage and, in some instances, an oil
prevents rapid brush wear in the battery-charging
temperature gage. These instruments are mounted on
alternator. If lights or other electrical equipment are
a separate panel.
connected into the circuit, the ammeter will show
discharge when these items are operating or the
engine speed is reduced.
Oil Pressure Gage
Tachometer
The oil pressure gage registers the pressure of the
lubricating oil in the engine. As soon as the engine is
The tachometer is driven by the engine and registers
started, the oil pressure gage should start to register. If
the speed of the engine in revolutions per minute
the oil pressure gage does not register at least the
(rpm).
minimum pressure listed under Running in the Engine
Operating Instructions, the engine should be stopped
and the cause of low oil pressure determined and
Engine Starting Motor Switch
corrected before the engine is started again.
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
Water Temperature Gage
the starting motor. As soon as the engine starts, release
the switch.
The engine coolant temperature is registered on the
water temperature gage.
Stop Knob
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
Fig. 1 - Typical Instrument Panel
In an emergency or if after pulling the stop knob, the
engine continues to operate, the emergency stop knob
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