Woodward UG-10 Dial, Installation And Operation Manual, Page: 34 / 62

UG Dial Governor Manual 03040
28 Woodward
To change oil, remove the drain plug and drain out the old oil. Flush the
governor by filling it with fuel oil, and with the prime mover running at low
speed, cycle the governor by opening the needle valve two or three turns.
Let the governor hunt for a minute or two, then stop the engine and drain the
governor. Flush the governor once again. Refill the governor with oil (see
Chapter 2, Oil Supply).
Restart the engine and reset the compensation adjustment and needle
valve.
6.
Check that the drive to the governor is correctly aligned and free of
roughness, side loading, and excessive backlash.
Table 5-1. Troubleshooting Chart
Problem Possible Cause Correction
1. The prime mover
hunts or surges. A. The problem may be
originating in the governor or
prime mover. Block the throttle, fuel racks or steam valve in the
direction of increase fuel. (Never block the governor
output shaft in the direction that would prevent a
complete shutdown.) The same blocking action can
be performed by using the load limit knob on the
governor panel.
If hunting and/or surging continues while the
governor output shaft is blocked, the problem is in
the prime mover.
If, after removing the block, hunting and/or surging
starts again, the problem can be in the governor or
in the prime mover. Go through the compensation
adjustment procedure for the governor (see Chapter
4, Compensation Adjustments). If the problem is still
there, replace the governor with a replacement
governor. Go through the compensation adjustment
procedure for the replacement governor. If the
hunting and/or surging continues, the problem is in
the prime mover.
B. Compensation adjustments
incorrect. Adjust needle valve and compensation adjusting
pointer.
C. Dirty oil (sludge) in governor. Drain oil, clean governor, and refill.
D. Low oil level, which permits
air to enter and cause foaming.
This is evident in the governor
as spongy operation. Add oil to the mark on oil sight glass. If oil level
decreases and no external oil leaks can be seen on
the governor, check the drive shaft for oil leak.
If foaming continues, drain oil and refill using a
different type oil.
E. Oil varnish, which causes
sticking of parts. Repair governor.
F. Lost motion in engine linkage
or fuel pumps. Repair linkage and/or pumps.
G. Binding in engine-to-
governor linkage or fuel pumps. Repair and realign linkage and/or pumps.
H. Governor output shaft travel
too short to provide full fuel. Adjust travel until proper travel is obtained.
I. Spring on yield linkage to fuel
racks too weak. Install heavier spring.