Yanmar 4LHA-HTP Operation Manual page 364

Chapter 3 Fuel Injection Equipment
5. Injection Pump Construction and Operation
Control sleeve
Plunger barrel
Outlet port
ig. 4 Cutaway view of fuel delivery
:
fl
Speed Governing
Control lever
Flyweight
(
governor sleeve
Fig. 5 Cutaway view of speed governing
Cross coupling
Cam disk Magnet valve
Distributor
head
Delivery valve
Control lever shaft
1^ Governor spring
Retaining pin
Governor
lever
^1 assembly
Ball joint
Plunger
Control sleeve
Because the plunger rotates and reciprocates
simultaneously, suction of the fuel oil into the
pressure chamber, pressurization in the pres-
sure chamber and delivery into the engine cyl-
inder are all possible.
Inlet port
The governor is located in the upper part of the
injection pump chamber. Four flyweights and a
governor sleeve are held in the flyweight hold-
er, which is mounted on the governor shaft.
The flyweight holder is rotated and accelerated
by the drive shaft gear, through rubber dam-
pers.
The governor lever assembly is supported by
pivot bolts in the pump housing, and the ball
joint at the bottom of the lever assembly is in-
serted into the control sleeve, which slides
over the outside surface of the plunger. The
top of the lever assembly {the tension lever) is
connected to the governor spring by a retaining
pin, while the opposite end of the governor
spring is connected to the control lever shaft.
The control lever shaft is inserted into the gov-
ernor cover and a control lever is attached to
the control lever shaft. The accelerator pedal is
connected directly to the control lever by a link-
age, and the governor spring set force changes
in response to the control lever position (i.e.
accelerator pedal position).
Injection quantity control is governed by the
mutually opposing forces of the
centrifugal force and the governor spring's set
force.
The
changes in response to engine speed, acts on
the
sleeve.
The governor spring's set force, which is de-
pendant on control lever position, i.e. accelera-
tor pedal position, acts on the governor lever
through the retaining pin.
3-1-7
flyweights' centrifugal
governor lever through
• 4LHA Serie
flyweights'
force, which
the governor