Service Manual

Indicator Lights, Buzzers and Gauges
Oil Pressure Light and Buzzer
Oil pressure lamp and buzzer should come on when the
ignition
key switch is in the RUN position with the engine
not running or if the oil pressure switch closes during
operation - oil pressure below 7 psi (0.5 kg/cm
2
).
Test the light and buzzer by disconnecting the wire from
oil
pressure switch and grounding it against the engine.
The light and buzzer should come on when the wire is
grounded with the ignition switch in the ON position.
Ammeter
Check the ammeter by comparing it to another amme-
te
r. Replace it if it registers incorrectly.
Glow Indicator
(Groundsmaster 322-D/325-D only)
The glow indicator should glow red after holding the
glow plug switch on for approximately 20 seconds.
Test the indicator by disconnecting the wires and check-
ing fo
r continuity across the terminals.
Hourmeter
Test the hourmeter by connecting a 12 volt battery so
the
positive (+) battery terminal is connected to the
positive terminal on the hourmeter. Connect the nega-
tive (–) battery terminal to the negative (–) terminal on
the alternator. The hourmeter should operate as
12 V.D.C. is applied between the terminals.
Engine Temperature Gauge and Fuel Level Gauge
To test a gauge, use a commercial gauge tester. If a
com
mercial gauge tester is not available, substitute a
new gauge or test the sending unit.
Testing P
age 6 - 26 Groundsmaster
®
300 Series