Engine Protection Devices; Oil Pressure Switch; Thermo Switch; Air Cleaner Indicator - Mitsubishi S4S-DT Operation & Maintenance Manual

Engine protection devices

The engine protection device is a device to prevent the engine from the accident by generating the alarm when
abnormality occurs. Stop the engine if the protection device is activated, investigate the cause of abnormality and
restore it. When the cause of abnormality is unknown, contact a dealer of Mitsubishi Heavy Industries, Ltd. The
installed protection devices, type (set value) or shapes varies according to the specifications.

Oil pressure switch

The oil pressure switch activates the alarm system or
stops the engine suddenly when the engine oil pres-
sure becomes abnormally low.

Thermo switch

The oil pressure switch generates an alarm when the
engine coolant temperature becomes high and
reaches the specified temperature.

Air cleaner indicator

The air cleaner indicator alarms with its red signal
when air cleaner elements become clogged, the differ-
ence in pressure between front air cleaner and rear air
cleaner, and reaches the specified value. The signal
indicates only, and does not generate an alarm,
Therefore, the periodic visually inspection is needed.
Press the reset button on the top of air cleaner indica-
tor and restore the signal after cleaned the air cleaner
indicator or replaced with a new one.
Oil pressure switch
Fig. 2-21 Oil pressure switch
Thermo switch
Fig. 2-22 Thermo switch
Reset button
Signal
(red)
Fig. 2-23 Air cleaner indicator
Chapter 2 NAME OF PARTS
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