Draining The Fuel - Yamaha F80B Service Manual

FUEL
4. Disconnect the pressure regulator hose,
and then connect the special service
tools to the pressure regulator.
WARNING
• When connecting the fuel pressure
gauge, first cover
between the gauge and the adapter with
a clean, dry rag to prevent fuel from
leaking out.
• Gently screw in the gauge until it is
firmly connected.
Fuel pressure gauge: 90890-06786
Fuel pressure gauge adapter B:
90890-06942
Vacuum/pressure pump gauge set:
90890-06756
5. Start the engine and let it idle.
6. Check that the fuel pressure reduces
when vacuum pressure is applied to the
pressure regulator. If the fuel pressure
does not reduce, replace the pressure
regulator.
4-15
Fuel system
S6D84200
the connection
WARNING
• Before measuring the fuel pressure,
make sure that the drain screw is tight-
ened securely.
• Do not loosen the drain screw while
measuring the fuel pressure. Loosening
the drain screw can cause fuel to spray
out creating a fire hazard.
• After measuring the fuel pressure, cover
the end of the hose with a clean, dry rag,
point the hose downward, and then
loosen the drain screw to drain the
remaining fuel from the hose and gauge.
• When storing the fuel pressure gauge,
make sure that the drain screw is tight-
ened securely.
NOTE:
When the vacuum pressure reaches the
specified level, the fuel pressure reduces.

Draining the fuel

1. Remove the cap 1.
2. Cover the pressure check valve a of the
vapor separator with a rag, and then
press in the pressure check valve a
using a thin screwdriver to release the
fuel pressure.
WARNING
Always reduce the fuel pressure in the
high-pressure fuel line before servicing
the line or the vapor separator. If the fuel
pressure is not released, pressurized fuel
may spray out.
3. Place a container under the vapor sepa-
rator drain hose, and then loosen the
drain screw 2.
4. Drain the fuel from the vapor separator
drain hose by pressing the pressure
check valve using a thin screwdriver.
6D93G11