Doosan G643, Руководство по обслуживанию

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G643(E) Service Manual 254 Appendix
Fuel Gauge
In figure 5 a visual fuel gauge is used to show the
fuel level in the tank. A mechanical float mechanism
detects the liquid propane level. A magnet on the
end of the float shaft moves a magnetic pointer in
the fuel gauge. Some units have an electronic
sending unit using a variable resistor, installed in
place of a gauge for remote monitoring of the fuel
level. The gauge may be changed with fuel in the
tank.
DO NOT REMOVE THE FOUR LARGE
FLANGE BOLTS THAT RETAIN THE FLOAT
ASSEMBLY, WITH FUEL IN THE TANK!
CAUTION
It is not a legal practice to fill the tank through
the liquid contents gauge.
In some applications a fixed tube fuel indicator is
used in place of a float mechanism. A fixed tube
indicator does not use a gauge and only indicates
when the LPG tank is 80% full. The fixed tube
indicator is simply a normally closed valve that is
opened during refueling by the fueling attendant.
When opened during refueling and the tanks LPG
level is below 80%, a small amount of vapor will exit
the valve. When the LPG tank level reaches 80%
liquid propane will begin exiting the valve in the form
of a white mist (Always wear the appropriate
protective apparel when refueling LPG cylinders). In
order for this type of gauge to be accurate, the tank
must be positioned properly. When full (80% LPG)
the valve is closed by turning the knurled knob
clockwise. Typically a warning label surrounds the
fixed tube gauge which reads
STOP FILLING
WHEN LIQUID APPEARS.
Service Valve
The service valve is a manually operated valve
using a small hand wheel to open and close the fuel
supply to the service line (fuel supply line). The
service valve installs directly into the tank and has
two main categories, liquid and vapor service valves.
Liquid service valves used on portable LPG tanks
use a 3/8” (3/8” NPT) male pipe thread on the
service valve outlet for attachment of a quick
disconnect coupler.
An excess flow valve is built into the inlet side of the
service valve as a safety device in case of an
accidental opening of the service line or damage to
the service valve itself. The excess flow valve shuts
off the flow of liquid propane if the flow rate of the
liquid propane exceeds the maximum flow rate
specified by the manufacturer.
CAUTION
When the tank is in use the service valve should
be completely open. If the valve is partly open,
the vehicle may not be getting enough fuel to
operate efficiently.
In addition to possibly starving the engine for
fuel, a partly open valve may restrict the flow
enough to prevent the excess flow valve from
closing in the event of a ruptured fuel line.
Outlet
Excess Flow
Valve
Figure 6