Yamaha F400A 2022 - Disassembling the Fuel Hose Assembly; Checking the Fuel Strainer; Checking the Relief Valve (High-Pressure Fuel Pump)

Fuel hose, feed valve, relief valve, and fuel strainer
6-14
Disassembling the fuel hose
assembly
1. Remove:
•Clamp “1”
TIP:
Make sure that the protrusion “a” on the clamp
fits in the slot “b” in the tool “2”.
Checking the fuel strainer
1. Check:
•Fuel strainer
Cracked/damaged → Replace.
2. Check:
• Strainer element
Dirt/residue → Replace.
TIP:
It is not necessary to remove the fuel strainer
from the fuel hose when checking the strainer
element.
a. Slide the retainer “a” outward.
b. Remove the cap “b”, and then remove
the strainer element “c”.
3. Check:
• Holding pressure
Out of specification → Replace the fuel
strainer.
a. Connect a pressure pump “1” to the
fuel inlet “a”.
b. Block the fuel outlet “b” using a rubber
plug “2”, and then apply the specified
positive pressure.
Checking the relief valve (high-
pressure fuel pump)
1. Check:
• Relief valve holding pressure
Out of specification → Replace.
a. Connect a pressure pump “1” to the
fuel outlet “a”.
2
1
a
b
2
2
Holding pressure (positive pres-
sure)
300.0 kPa (3.00 kgf/cm², 43.5
psi)
Pressure pump “1”
(commercially available)
Holding pressure (positive pres-
sure)
490.0 kPa (4.90 kgf/cm², 71.1
psi)
b
a
c
300
400
500
1
a
b
2