Doosan GC25P-3 User Manual

- 97 -LP Engine G430(3.0L) LP Fuel System (Low Emission Version)
GOVERNOR SYSTEM
General Description
Governors are regulating devices which allow engine
speed to remain constant in both loaded and unloaded
operating conditions. There are several different types
of governor designs such as mechanical, hydraulic,
electric and velocity used to control engine speed.
Governors normally control engine speed by limiting
the amount of air and fuel entering the engine. On
velocity governors, the air flowing through the
carburetor strikes the governor valve. This governor
valve would close off completely if not for the opposing
action of the cam and governor spring. When the
spring tension and air flow are balanced, governing
action takes place and engine speed remains fixed at
that point. When additional load is applied, the engine
speed drops and the velocity of the fuel mixture is
reduced. With lower air velocity through the gover-nor
the pressure against the governor valve is reduced
and the spring opens the governor valve to supply
more fuel to the engine to meet the increased load
demand. This allows a constant engine speed to be
maintained with or without a load on the engine.
Components
Figure 8-7 Governor Installation
Figure 8-8 Governor Mechanism
In order for the velocity governor to control engine
speed within a specified range, a control mecha-nism
is required to limit the amount of fuel entering the
engine. On the Aisan Governor this function is
performed by the governor valve. The governor valve
is mounted on an off-set shaft, which when
encountering high air flow through the venturi, will
attempt to close, thus limiting the amount of air and
fuel entering the engine (figure 8-7). The closing force
is opposed by a cam and spring mechanism (figure 8-
8). When the opposing forces are balanced, the
governor valve stops at a fixed posi-tion and maintains
engine speed at a constant setting. The opening angle
of the governor valve is adjusted by means of an
adjusting screw.
7226-400-016
7226-400-015

Doosan GC25P-3 Specifications

General

Brand	Doosan
Model	GC25P-3
Category	Engine
Language	English