Onan MDKBH Series, Service Manual

Page: 48 / 90

6-7
GOVERNOR ACTUATOR
WARNING
Accidental or remote starting can
cause severe personal injury or death. Before
removing a panel or access door, disconnect
the negative (–) cable at the battery to prevent
the engine from starting.
The position of the rotor in governor actuator A12
(Figure 6-6) is determined by the modulated pulse
width of the current supplied by the genset control-
ler.
Checks and Tests
When the governor appears to be malfunctioning—
see Troubleshooting (Section 11)—remove the
front and top access doors and lintel (p. 5-1) and the
governor actuator cover (p. 6-7). Observe the ac-
tuator rotor while cranking. (Remember to re-attach
the leads after removing the cover.) The governor
probably is not the problem if the rotor rotates
smoothly through about 1/2 inch (12 mm). If it does
not:
1. Check for binding in the governor mechanism
by pushing the actuator rotor clockwise by hand
(against the fuel rack return spring). It should
rotate smoothly about 1/2 inch (12 mm) and re-
turn smoothly.
A. If the governor binds or catches , re-
move the bearing carrier and stator and
look for signs of physical contact between
rotor and stator and service as necessary.
If there are no signs of contact, remove the
governor base. Replace the base or ser-
vice the internal engine governor mecha-
nism, as necessary, in accordance with the
engine Workshop Manual (p. 6-1).
B. If the governor rotates smoothly by
hand , check resistance across the actua-
tor terminals with an accurate digital ohm-
meter. If resistance is not between 1.7 and
2.8 ohms, replace the actuator stator.
C. If the governor still does not function ,
disconnect connector P1 (black) from the
genset controller (p. 9-1) and measure re-
sistance between Pin 5 and A12+ and be-
tween Pin 4 and A12–. If either lead is
open, check for a missing, bent or cor-
roded pin or faulty wiring and repair as nec-
essary.
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by any means, is strictly prohibited.