Hobart 6921 Series Operation And Maintenance Manual page 106

OM-2040 / Operation and Maintenance Manual
90D20 / Generator Sets
Engine and Controls(cont.)
Trouble, Symptom & Condition
6. Engine will not come "up" to
governed speed in GEN mode.
Chapter 3-1
Page 14
Test or Inspection
a. 12-V DC power not
reaching governor control
box for following reasons:
b. Engine circuit fuse (26, Fig.
1) is blown.
c. Oil pressure switch (S53)
(located behind oil gage) is
defective.
d. Defective operating mode
switch (18, Fig. 1)
e. Governor linkage binding or
governor throttle sticking.
f. Defective or mis-adjusted
magnetic pickup.
g. Defective actuator.
Corrective Action
Apply 12-V DC directly to
terminal "1" on governor control
box. If engine comes-up to
speed, check
following:
Replace fuse (10 Amp).
Check switch and replace if
defective.
Check switch. Replace if
defective.
Check governor linkage and
throttle shaft for binding and
sticking. Repair as required.
The control unit may not be
receiving a signal from the
magnetic pickup and the "fail
-safe" feature of the unit may be
functioning to prevent any
signal from reaching the
actuator. To check the mag-
netic pick-up, disconnect pickup
from control unit and connect a
high impedance AC voltmeter to
the pickup output leads. Crank
engine but don't start. Voltage
reading should be a minimum of
(1) volt. If no voltage or low
voltage is indicated, check
pickup adjustment [See 2-3,
Para. 4, E, (2)]. If pickup is
properly adjusted and voltage is
still zero, replace pickup.
Apply 12-V DC to the two
actuator input leads. Actuator
lever should move immediately
to full speed position. If lever
does not move, replace actuator
February 28/94 Revised