Service Manual

GLOSSARY
3 - 6 Demystification Glossary
Testing
1. With the meter still connected to the harness, turn
the key to the “RUN” position.
2. Verify the conditions in the table below. If they are
not met, replace the voltmeter as it is not
serviceable (Figure 6).
Hourmeter
Figure 7 mvc-110
Purpose
The hourmeter keeps track of the actual engine hours
(Figure 7). This is accomplished by connecting the
hourmeter to the engine oil pressure switch.
How it Works
Since a normal clock might be affected by variations in
voltage and current, the hourmeter is made up of a
combination of an electric “winder” and a mechanical
clock movement. When power is applied, a coil is
energized to wind the movement. The movement
unwinds in about two seconds. As it finishes its
rotation, it re-energizes the coil so that the cycle can
start over.
Testing
Verify that 12 volts is present across the two terminals
when the engine is running. If so, and the meter is not
running, replace the meter. If 12 volts is not present,
check the connections and the engine oil pressure
switch. The meter is a permanently sealed unit and is
not repairable.
Terminal Condition
I 12 volts DC +/- 20%
G 0 volts DC
Glossary