TM 5-3895-346-14
INSTRUMENTS
ENGINE OVERHAUL
INSTRUMENTS AND TACH01ETER DRIVE
The instruments (Fig. 1) generally required in the
operation of a diesel engine consist of an oil pressure
gage, water temperature gage, an ammeter and a
mechanical tachometer.
Instruments with slotted
cases are available for use with lighted dashes. Also,
closely related and usually installed in the general
vicinity of these instruments are certain controls
consisting of an engine starting switch, engine stop
knob and an emergency stop knob.
All Torqmatic converters are equipped with an oil
pressure gage and, in some instances, with an oil
temperature gage. These instruments are mounted on
a separate panel.
Instruments, throttle control, and engine starting and
stopping controls are mounted in various locations
depending upon the particular use of the engine.
Figure 1. Typical Instrument Panel
Antivibration Instrument Mountings
Antivibration mountings are used in many places to absorb engine vibration in the mounting of instruments,
drop relays, tachometers, etc. When it may become necessary to service a part secured by rubber mounts,
care should be exercised, during removal and installation of the part, so twist is not imposed into the rubber
mount diaphragm. At the time the part is removed from the engine for service, the mounts should be inspected
for damage and replaced, if necessary.
The attaching screw, through the center of the mount, must be held from turning during final tightening of the
nut. Support the screw and tighten the nut only. If this screw turns, it will preload the rubber diaphragm in
torsion and considerably shorten the life of the mount.
Oil Pressure Gage
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 in the Operating Condition, the engine should be stopped and the cause of the low oil
pressure determined and corrected before the engine is started again.
Current oil pressure gages have male threads and require female fittings. When replacing a former gage with
female threads, a new mounting clamp and connector must be used.
Water Temperature Gage
The engine coolant temperature is registered on the water temperature gage.
Incorrect coolant temperature readings will be registered if the gage assembly is incorrectly installed or the
capillary tube is damaged.
To prevent damage to the gage assembly from vibration, the capillary tube must be securely fastened to the
engine the
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