Multi-Port System
Description
!
WARNING
Be careful when cleaning flame arrestor and
crankcase ventilation hose; gasoline is extreme-
ly flammable and highly explosive under certain
conditions. Be sure that ignition key is OFF. DO
NOT smoke or allow sources of spark or open
flame in area when cleaning flame arrestor and
crankcase ventilation hose.
The MerCruiser EFI Fuel System consists of a fuel
supply, water separating fuel filter, mechanical fuel
pump, vapor separator tank (VST), electric fuel
pump, injector fuel filter, fuel rail, pressure regulator,
fuel injectors, throttle body and throttle position (TP)
sensor.
Sight Tube to
Throttle Body
! WARNING
Be careful when changing fuel system compo-
nents; gasoline is extremely flammable and high-
ly explosive under certain conditions. Be sure
that ignition key is OFF. DO NOT smoke or allow
sources of spark or open flame in the area while
changing fuel filter(s). Wipe up any spilled fuel
immediately.
to Intake
!
WARNING
Be sure that the engine compartment is well ven-
tilated and that no gasoline vapors are present to
avoid the possibility of fire.
!
WARNING
Fuel is drawn from the boat’s fuel supply (tank),
throughawaterseparatingfuelfilter,byamechanical
fuel pump mounted on and driven by a seawater
pump, and is delivered to the vapor separator tank
(VST).
Make sure no fuel leaks exist, before closing en-
gine hatch.
! CAUTION
The VST consists of a reservoir, float, needle and
seat assembly, fuel pump pickup screen, electric fuel
pump. The electric fuel pump located in the VST,
pumps the fuel rail supplying pressurized fuel to the
fuel injectors.
Fuel pressure MUST BE relieved before servicing
high pressure component in the fuel system.
! CAUTION
Apressureregulatorlocatedonthefuelrailmaintains
a constant fuel pressure in the fuel rail. The fuel bled
off from the pressure regulator is delivered back to
the VST.
DO NOT operate engine without cooling water
being supplied to water pickup holes in gear
housing, or water pump impeller will be damaged
and subsequent overheating damage to engine
may result.
The throttle body is the component of the system
which supplies the air required for optimum fuel com-
bustion. The throttle body consists of a housing, two
throttle plates, throttle plate linkage, idle air control
(IAC) valve and throttle position (TP) sensor.
The following information MUST BE adhered to
when working on the fuel system:
•
Always keep a dry chemical fire extinguisher
at the work area.
Service Precautions
•
Always install new O-rings when assembling
fuel pipe fittings.
!
WARNING
•
•
DO NOT replace fuel pipe with fuel hose.
Always disconnect battery cables from battery
BEFORE working on fuel system to prevent fire
or explosion.
DO NOT attempt any repair to the fuel system
until instructions and illustrations relating to
that repair are thoroughly understood.
•
Observe all Notes and Cautions.
Index
5C-154 - ELECTRONIC FUEL INJECTION (MULTI-PORT AND THROTTLE BODY)
90-823224--2 796
| Categories | Mercury MerCruiser Manuals |
|---|---|
| Tags | Mercury MerCruiser 454 CID, Mercury MerCruiser 502 CID |
| Model Year | 1993, 1994, 1995, 1996, 1997 |
| Download File |
|
| Document File Type | |
| Copyright | Attribution Non-commercial |
(4 votes, average: 4.5 out of 5)
Marine readers have rated 1993 1997 Mercury-MerCruiser GM V8 454 CID 7.4L and 502 CID 8.2L Marine Engines Service Manual Number 16 4.5 out of 5.0 based on 4 product reviews. Hugely helpful service manual! Perfect. Thank you!
Manuals are all Important for Technician
This book is invaluable if you do your own repairs. Great book.
Could not find a copy until a search brought me here.
Excellent print.
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