Components Of Fuel Feed System; Fuel Pump (Low Pressure Mechanical Pump); Vapor Separator - TOHATSU MFS25 Service Manual

6. Components of Fuel Feed System

1) Fuel Pump (Low Pressure Mechanical Pump)

Fuel pump is diaphragm pump that is operated mechanically by cam shaft.
Pump base is plastic components shuts off heat of engine block to protect fuel pump from engine heat.
a IN : Fuel from Filter/Tank
b OUT : Fuel Outlet to Vapor Separator

2) Vapor Separator

Vapor separator feeds only liquid fuel for internal fuel feed pump (FFP) (electrical high pressure pump). Fuel that is fed
from fuel pump (low pressure mechanical pump) is sent to upper part of vapor separator, where it is controlled with needle
valve/float ass'y. High pressure fuel from fuel feed pump (FFP) is fed to fuel cooler, high pressure fuel filter, fuel rail and
fuel injector. Excessive fuel is returned to vapor separator by fuel regulator.
e
d
a Fuel from Fuel Pump
b Needle Valve and Float
c Fuel Feed Pump (FFP)
d Fuel to Fuel Cooler
e Fuel Regulator
f Fuel Cooler
g Air to Air Vent
h Excessive Fuel from T Nipple
25/30 2006
b
OUT
g
a
a
IN
e
OUT
d
f
c
h
g
a
IN
b
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