Service Manual

6-16 Z Master 597 Diesel Series Service Manual
6
ELECTRICAL
OIL PRESSURE SWITCH
Purpose
When the oil pressure drops, the switch activates an
audible alarm which alerts the operator to shut the
engine down immediately.
Located on the right hand side of the engine block,
above the oil dipstick tube (Fig. 371).
Fig 371 DSC-2558
If the audible alarm operates continuously (pulse mode)
when the engine is running, disconnect the switch lead.
If the alarm stops, the pressure switch is bad. The switch
can also be tested with an ohmmeter. There should be
continuity between the wire terminal and ground with the
engine not running, and no continuity when the engine is
running.
Fig 372 DSC-2557
The oil pressure switch is a normally closed switch.
When the engine is running, oil pressure builds and
opens the contact in the switch. If the engine oil
pressure drops, the contacts in the switch close,
grounding the audible alarm, which alerts the operator to
shut the unit down immediately (Fig. 372).
How It Works
Location
Testing