Zontes ZT125-M 2022, Maintenance Manual

Page: 83 / 218

83 / 218
d. Pull down the surrounding bottom plate in the center of
the front part (near the front wheel) with one hand, and pull
down the surrounding bottom plate after pulling about
20mm (0.8 in) toward the rear wheel with the other hand.
There is a bracket at the place shown in the small picture, so
it cannot be pulled down directly.
e. Unplug the fuel pump and start the engine at idle speed
until the engine stops. Turn the engine stop switch to " ",
power off the vehicle and lock the vehicle. Early production
vehicles did not contain high- pressure fuel pipe brackets①.
f. Pull out the high-pressure oil pipe from the bracket at
the cylinder head.
g. Pull out the high-pressure oil pipe in the direction of the
arrow after pressing down the anti-dropping lock. Note that
there are high-pressure fuel pipe brackets and cable ties at
the intake manifold of vehicles produced after March 2021.
The vehicles produced before are only lashed with cable ties.
h. After replacing the new high-pressure oil pipe, refer to
the disassembly steps to restore it.
3. Fuel pump
3.1 Use oil pressure gauge to measure fuel
pressure
a. Refer to steps a to k of "Remove stepper motor and
clean up carbon deposits" in the throttle valve body, first
remove the seat cushion and storage box components, and
remove them as shown in the figure below.
b. Unplug the fuel pump and start the engine to idle until
the engine stops. Turn the engine stop switch to " ",
power off the vehicle and lock the vehicle. After putting on
waterproof and oil-proof gloves, press the anti-trip lock and
pull out the high-pressure oil pipe in the direction of the
arrow.
c. Connect the high-pressure oil pipe of the original car to
the pressure gauge, and find another high-pressure oil pipe
to connect the pressure gauge and the fuel injector.
Start the vehicle, let the engine run at idle speed, and
measure the fuel pressure. M125/310 the standard pressure
is: 300±10kPa (3.06±0.1Kgf/cm2, 43.5±1.45 psi). Check valve
performance: hold the pressure for 1 minute, the pressure
should be ≥240kPa (2.45Kgf/cm2, 34.8 psi).
3.2 Simple test of fuel pump
If you do not have the special equipment conditions, you
can do a simple test.
After the vehicle is in the stalled state, unlock the vehicle
and turn on the stall switch. If you do not start the engine,
you should be able to hear the sound of the fuel pump; or
pinch the high-pressure fuel pipe from the bottom with your
hands, and you should feel obvious pressure. Take care to