WOODWARD UG8 LEVER GOIVERNORS
SCHEMATIC OF UG8 LEVER GOVERNOR
The Woodward UG8L is the standard governor
An accumulator is used to keep a constant oil
used on Industrial Engines. Standard location for the
pressure of approximately 830 kPa (120 psi) to the top of
governor is on the right side of the front housing; with an
the power piston and to the pilot valve.
attachment gear group it can be located on the left side.
The power piston is connected by a linkage
The UG8 Lever Governor is a mechanical-
system to one side of the output terminal shaft. There is
hydraulic governor. A hydraulic activated power piston is
oil pressure on both the top and bottom of the power
used to turn the output terminal shaft of the governor.
piston. The bottom of the piston has a larger area than
The terminal shaft is connected by linkage to the fuel
control torsion shafts. The rotation of the fuel control
torsion shafts controls rack movement at each fuel
Less oil pressure is required on the bottom than
Make reference to FUEL INJECTOR
on the top to keep the piston stationary. When the oil
CONTROL LINKAGE. The governor oil pump and
pressure is the same on the top and bottom of the
ballhead are driven by a bevel gear set in the governor
piston, the piston will move up and cause the output
drive housing. The bevel gear set is driven by the front
terminal shaft to turn in the increase fuel direction. When
oil pressure on the bottom of the piston is directed to the
sump (drain), the piston will move down and cause the
The oil pump gives pressure oil to operate the
output terminal shaft to turn in the decrease fuel
power piston. The drive gear of the oil pump has a
direction. Oil to or from the bottom of the power piston is
bushing in which the pilot valve plunger moves up and
controlled by the pilot valve.
down. The driven gear of the oil pump is also the drive
for the ballhead.
The pilot valve has a plunger and bushing. The bushing
is turned by the governor drive shaft. The rotation of the
bushing helps reduce friction between