Doosan GC25P-3 User Manual

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LP Engine G430(3.0L) LP Fuel System (Low Emission Version)
Fuel Lock (Electric)
Since LPG is held in the fuel storage container
under pressure a fuel lock is required to
automatically control when fuel flows out of the
container. The electric fuel lock consists of a valve
normally held closed by spring pressure and an
electrical solenoid used to open the valve. The fuel
lock requires an electrical signal from the engine
cranking or running to open. If the engine stops or
is turned off fuel flow automatically stops. This is the
second of three safety locks incorporated into the
DAEWOO LP Engine System.
When the liquid outlet valve in the fuel container is
opened liquid propane flows through the liquid
service line to the fuel lock. Liquid propane enters
the fuel lock through the 1/4” NPT liquid inlet port.
Since the fuel lock valve is normally held closed by
spring pressure the flow of liquid propane stops at
this time. When the engine is cranked over an
electrical signal is generated. The electrical signal
is used to operate an electrical relay which in-turn
operates the fuel lock solenoid. When current flows
through the windings of the solenoid a magnetic
field is created. The strength of this magnetic field
is sufficient to lift the valve off of its seat against
spring pressure. With the valve open liquid
propane, at tank pressure, flows through the outlet
to the pressure regulator.
.
Pressure Regulator/Vaporizer
The regulator is two staged, pressure
regulator/vaporizers. The regulator is normally
closed, they require a vacuum signal from the mixer
to allow fuel to flow. If the engine stops or is turned
off fuel flow automatically stops. This is the second
of three safety locks incorporated into the
DAEWOO LP Engine System.
The amount of fuel flowing from the regulator is
proportional to the strength of this vacuum signal.
When the regulator receives the desired vacuum
signal from the mixer it allows propane to flow to the
mixer. As the propane flows through the regulator
the pressure is reduced in two stages from tank
pressure to slightly less than atmospheric pressure.
As the pressure of the propane is reduced the liquid
propane vaporizes and refrigeration occurs inside
the pressure regulator. To replace heat lost to
vaporization, liquid propane pressure regulators are
designed to connect to the vehicle cooling system.
The heat from the engine coolant replaces heat lost
to the vaporization process.

Doosan GC25P-3 Specifications

General

Brand	Doosan
Model	GC25P-3
Category	Engine
Language	English