4.3L/5.3L/6.

2L/LT4
MEFI 7 DIRECT INJECTION
ENGINE OWNER’S MANUAL
VERSION 4
 Table of Contents
Section 1: Introduction Half Closed Cooled Engines. ...............................................21-22 Section 13: Installation Instructions
Proposition 65.......................................................................1 Full Closed Inboard Jet Engines. ...............................................23 Engine Compartment. ..............................................................41
Safety Warnings.....................................................................1 Engine Mounting...................................................................41
Section 10: Engine Maintenance
Replacement Parts. ..................................................................1 Engine Rotation. ...................................................................41
Scheduled Maintenance by Owner...............................................24
Safe Boating..........................................................................2 Engine Bed..........................................................................41
Scheduled Maintenance by Qualified Technician...............................25
Warranty. .........................................................................2-6 Cooling System. ..............................................................41-42
Crankcase Oil Change.............................................................26
Emission-Related Installation Instructions. ....................................42
Section 2: Safe Boating Oil Filters...........................................................................27
Exhaust Piping.................................................................42-43
Carbon Monoxide Exposure........................................................6 Flame Arrestor.....................................................................28
Electrical Connection..............................................................43
Section 3: Engine Identification G-Force Fuel System..............................................................28
Batteries.............................................................................43
Engine Type. ..........................................................................7 Battery Cables......................................................................29
Dual Engines........................................................................43
Model Specifications. ...............................................................8 Multiple Engine Battery Precautions - EFI.....................................29
Battery Isolators. .................................................................43
Alternator Belt Tension...........................................................29
Section 4: Electronic Sequential Fuel Injection Engine Battery Specifications.....................................................44
Sea Water Pump Impeller Replacement. ........................................29
Information. ...........................................................................9 Battery Cable Length Requirements. ............................................44
Closed Cooling System. ..........................................................30
Special Fuel Instructions for 6.2 550 HP Engines. .......................44
Section 5: Engine Alarms and Instrumentation Filling Closed Cooling System..............................................30-31
LSA Airboat Installation Notes..................................................45
Digital Alarms......................................................................10 Section 11: Engine Diagnostics and Codes.........................32-34 Adapter Harness. ..................................................................46
Instrumentation.....................................................................11 Heater Connections................................................................47
Section 12: Trouble Shooting
Section 6: SSVEC Fuse and Relay Enclosure.......................12-15 Engine Will Not Turn Over......................................................35 Prestart Checklist..................................................................48
Engine Cranks But Will Not Start. ............................................35 Potentiometer Operation..........................................................49
Section 7: Precautions
Oil Level. ...........................................................................16 Engine Runs Poorly at High RPM...............................................36 Warranty Registration Transfer. ............................................50
Hydrolock...........................................................................16 High Speed Miss...................................................................36
Service Log. .....................................................................51-53
Fuel System - Rich. ...............................................................37
Section 8: Engine Operating Instructions Fuel System - Lean. ...............................................................37
Gasoline Requirements............................................................17 Poor Fuel Economy. ..............................................................37
Oil Requirements...................................................................17 Engine Starts and Stops..........................................................38
Starting Engine EFI................................................................17 Oil Pressure - Low................................................................38
Engine Break-In/25 Hour Inspection.....................................17-18 Oil Pressure - High. ..............................................................38
Section 9: Winterization Excessive Oil Consumption.......................................................39
4.3/5.7L Raw Water Cooled Engines........................................19 Engine Overheating. ...............................................................39
Full Closed Cooled Engines......................................................20 Water in Engine Cylinder or Base...............................................40

i www.MarinePowerUSA.com
 1. Introduction
Marine Power would like to thank you again for your pur- Safety Warnings Replacement Parts
DANGER
chase. The pleasure and peace of mind derived from your new

DANGER
Use of replacement parts (i.e. automotive, after-market, etc.) in the
engine is in direct proportion to the amount of care that it is

DANGER
electrical, ignition and fuel systems, which are not U.S. Coast Guard
given. We have tried to include as much as possible in our Engine
approved, could cause a fire or explosion hazard and must be avoided.
Owner’s Manual to help you as the customer. READ THIS Signals serious damage, failure or breakdown of equipment;
MANUAL THOROUGHLY AND COMPLETELY before attempting severe injury or high probability of death to the user if proper Always request that genuine Marine Power engine replacement
to operate your Marine Power engine. We ask that you become precautions are not taken. This signal word is applied in extreme parts be used in any repairs or maintenance being performed on
familiar with the components and the maintenance schedules. If

DANGER
you have any questions or concerns regarding this manual or your
situations.
WARNING
WARNING
your engine(s).

newly purchased Marine Power engine, please feel free contact

WARNING DANGER
DANGER
your nearest Marine Power dealer or distributor.
Indicates a potential hazard which could result in personal injury. Electrical, ignition and fuel system components are designed
Proposition 65 and manufactured to comply with U.S. Coast Guard rules and

WARNING CAUTION
CAUTION
regulations to minimize the possibility of fire or explosion

CAUTION WARNING
hazard.
Indicates a hazard which could result in damage to equipment.

WARNING
The engine exhaust from this product contains chemicals
known to the State of California to cause cancer, birth defects
or other reproductive harm.
The LT4 Is a Premium 93 Octane REQUIRED engine. The

CAUTION
“Safety Warnings” and additional information or instructions are
used to alert the installer/operator of possible safety hazards in
engine will operate at significantly reduced power output with
CAUTION
octane levels down to 90. Operating the LT4 on fuel below

CAUTION
performing certain service or maintenance procedures incorrectly 90 Octane can result in engine damage and or failure! Such
or carelessly. failure will not be covered under warranty!
These “Safety Warnings” alone cannot eliminate the hazards
that they signal. Strict compliance with these warning instruc-
tions while performing service and maintenance procedures,
plus “common sense” operation, are major accident prevention
measures.

www.MarinePowerUSA.com 1
 1. Introduction
Safe Boating WARRANTY REGISTRATION MUST BE RECEIVED WITHIN 10 built and equipped to meet California and EPA’s stringent anti-smog
DAYS AFTER DATE OF PURCHASE BY FIRST OWNER. standards. Marine Power Holding LLC must warrant the emission control
The waterways are becoming increasingly crowded and, in order
system on your Inboard engine for the periods of time listed on the next
to enjoy them safely, the operator should acquaint himself/her- Please read the Limited Warranty document that is included
page, provided there has been no abuse, neglect or improper mainte-
self with safe boating practices. Boating safely and seamanship with your engine registration papers and in this manual. This
nance of your inboard engine.
ourses are offered by the following national and state organi- document explains your warranty coverage. Please note that no
zations: warranty repairs are to be performed without prior authorization Your emission control system may include parts such as fuel
from the Marine Power Distributor in your area. Contact your injection system, the ignition system and catalytic converter. Also
• Power Squadrons
selling dealer directly for any required warranty repairs. included may be hoses, belts, connectors and other emission-
• Coast Guard Auxiliary related assemblies.
For more information, you may also visit our web site at
• Red Cross www.marinepowerusa.com. Where a warrantable condition exists, Marine Power Holding LLC will
• State, provincial or local agencies in charge of water safety repair your inboard engine at no cost to you, including diagnosis, parts
Again, thanks for choosing Marine Power.
enforcement and labor.
CALIFORNIA AND U.S. ENVIRONMENTAL PROTECTION AGENCY
Marine Power recommends that all power boat operators attend EMISSIONS CONTROL WARRANTY STATEMENT
one of these courses.
Your Warranty Rights and Obligations
To help locate a course being offered near you, contact Boat
U.S. Foundation’s toll-free national boating safety hotline, The California Air Resources Board, U.S. E.P.A., and Marine Power
1-800-336-BOAT, and in Virginia, 1-800-245-BOAT. Holding LLC are pleased to explain the emission control system war-
ranty on your inboard engine. New Inboard engines must be designed,
The Federal Boat Safety Act of 1971 requires that registration of
marine products sold in the United States be maintained by the
manufacturer and dealers of those products. It is imperative that
Marine Power Holding LLC receive your WARRANTY REGISTRA-
TION/SEA TRIAL form properly completed for warranty purpos-
es and to comply with federal regulation. This registration also
enables us to contact you, if it should become necessary, to change
or improve the product for your protection.

2 www.MarinePowerUSA.com
 1. Introduction
Manufacturer’s Warranty Coverage TY OTHER THAN THAT STATED IN THE LIMITED WARRANTY.
UNDER NO CIRCUMSTANCES SHALL MARINE POWER BE LIABLE
Engine Type Power Electronic Mechanical TO THE CUSTOMER OR ANY OTHER PERSON FOR ANY CONSE-
Rating Components Components QUENTIAL, INCIDENTAL, ECONOMIC, DIRECT, INDIRECT, GENER-
Conventional - OEM Less than or equal to 3 Years or 480 Hours 3 Years or 480 Hours AL, OR SPECIAL DAMAGES ARISING OUT OF ANY BREACH OF
373 kW (500 HP) WARRANTY, EXPRESSED OR IMPLIED.
Hi-Performance - OEM Between 373 kW (500 HP) 3 Years or 150 Hours 3 Years or 150 Hours Owner’s Warranty Responsibilities
and 485 kW (650 HP) As the Inboard engine owner, you are responsible for the
Complete Engine Repower Less than or equal to 2 Years or 300 Hours 2 Years or 300 Hours performance of the required maintenance listed in your own-
373 kW (500 HP) er’s manual. Marine Power Holding LLC recommends that you
retain all receipts covering maintenance on your inboard engine,
Complete Engine Repower Between 373 kW (500 HP) 1 Year or 150 Hours 1 Years or 150 Hours
but Marine Power Holding LLC cannot deny warranty solely for
and 485 kW (650 HP)
the lack of receipts or your failure to ensure the performance
Special Applications All 1 Year or 150 Hours 1 Years or 150 Hours of all schedule maintenance. Marine Power highly recommends
that the selling dealer do Warranty Registration along with a
THIS AGREEMENT GIVES YOU SPECIFIC LEGAL RIGHTS, AND exclusion may not apply to you. This warranty gives you specific
completed Statement of Sea Trial in order to facilitate any
YOU MAY ALSO HAVE OTHER RIGHTS THAT VARY FROM JURIS- legal rights and you may also have other rights which vary from
warranty work necessary in the future.
DICTION TO JURISDICTION. state to state and country to country.
As the Inboard engine owner, you should however be aware that
THERE IS NO OTHER EXPRESS WARRANTY. IMPLIED WARRAN- THE FOREGOING REMEDIES ARE EXCLUSIVE. MARINE POWER
Marine Power Holding LLC may deny you warranty coverage if
TIES, INCLUDING THOSE OF MERCHANTABILITY AND FITNESS MAKES NO OTHER EXPRESS WARRANTY. MARINE POWER SHALL
your Inboard engine or part has failed due to abuse, neglect or
FOR A PARTICULAR PURPOSE, ARE LIMITED TO THE APPRO- IN NO CIRCUMSTANCES BE LIABLE IN CONTRACT, IN TORT OR
improper maintenance or unapproved modifications.
PRIATE WARRANTY PERIOD IN THE ABOVE TABLE, OR TO THE OTHERWISE FOR SPECIAL, INCIDENTAL OR CONSEQUENTIAL
EXTENT PERMITTED BY LAW, ANY AND ALL IMPLIED DAMAGES, WHETHER OR NOT FORESEEABLE. NO EMPLOYEE You are responsible for presenting your Inboard engine to a
WARRANTIES ARE EXCLUDED. LIABILITY FOR INCIDENTAL OR OR REPRESENTATIVE OF MARINE POWER IS AUTHORIZED TO Marine Power Holding LLC distribution center as soon as a prob-
CONSEQUENTIAL DAMAGES ARE EXCLUDED TO THE EXTENT MODIFY THIS WARRANTY, OR MARINE POWER’S STANDARD lem exists. The warranty repairs will be complete within a rea-
EXCLUSION IS PERMITTED BY LAW. Some states or countries do WARRANTY FOR ANY PRODUCT. sonable amount of time, not to exceed 30 days.
not allow limitations on how long an implied warranty lasts, and MARINE POWER DOES NOT AUTHORIZE ANY PERSON TO 1. Marine Power Holding LLC (“Marine Power”) warrants to
some states or countries do not allow the exclusion or limitation of CREATE FOR MARINE POWER ANY OBLIGATION OR LIABILI- the first owner purchasing at retail and all subsequent own-
incidental or consequential damages, so the above limitation and
www.MarinePowerUSA.com 3
 1. Introduction
ers, of every Marine Power Inboard marine engine manufac- for the remainder of the period. 8. Marine Power is liable for damages to other engine compo-
tured after January 1, 2008, that the emissions control devic- nents proximately caused by a failure under warranty of any
4. Any warranted part that is scheduled only for regular inspec-
es on Marine Power Inboard marine engines are free from warranted part.
tion in the written instructions in the Owner’s Manual will be
defects in materials and workmanship when manufactured warranted for the appropriate warranty period in the above 9. Throughout the appropriate warranty period in the table
and will remain so for the stated period in the above table. table. A statement in such written instructions to the effect of from the previous page Marine Power will maintain a supply
Marine Power warrants that each Marine Power Inboard “repair and replace as necessary” does not reduce the period of warranted parts sufficient to meet the expected demands
marine engine and factory installed accessories designed, of warranty coverage. Any such part repaired or replaced for such parts.
built and equipped with all applicable regulations adopted under warranty will be warranted for the remaining war-
by the Air Resources Board pursuant to its authority in Chap- 10. Any replacement part may be used in the performance of
ranty period. any warranty maintenance or repairs and will be provided
ters 1 and 2, Part 5, Division 26 of the Health and Safety
Code; and the U. S. Environmental Protection Agency pursu- 5. Any warranted part that is scheduled for replacement as without charge to the owner. Such usage will not reduce
ant its authority in Chapter 9 of Title 5 of the U.S. Code to be required maintenance in the written instructions in the Marine Power’s warranty obligations.
free from defects in materials and workmanship that cause Owner’s Manual will be warranted for the period of time 11. Add-on or modified parts, as defined in CCR, Section 1900
the failure of a warranted part to be identified in all material before the first scheduled replacement date for the part. If (b)(1) and (b)(10), Title 13, that are not exempted by the
respects to that part as described in the engine manufacturer the part fails before the first scheduled replacement, the part Air Resources Board will not be used. The use of any non-
application for certification. will be repaired or replaced by Marine Power at a warranty exempted add-on or modified parts by the ultimate purchas-
station. Any such part repaired or replaced under warranty
2. The warranty shall commence, on the date of delivery to er will be grounds for disallowing a warranty claim made
will be warranted for the remainder of the period to the first
the first retail purchaser or from the date the engine is first in accordance with this article statement. Marine Power will
scheduled replacement point for the part.
placed in service for demonstration or any other purpose not be liable under this statement to warranted failures of
prior to the sale to the first retail owner. However, in no event 6. Repair or replacement of any warranted part under the warranted parts caused by the use of non-exempted add-on
shall the duration of this warranty exceed three (3) years warranty provisions of the article will be performed at a or modified part.
measured from the original retail sale date. warranty station at no charge to the owner. Warranty services 12. The following parts are covered by this general emissions
and repairs will be provided at all Marine Power distribution
3. Any warranted part that is not scheduled for replacement warranty statement.
centers and trained marine dealers.
as required maintenance in the written instructions in the A) Fuel Metering System
Owner’s Manual will be warranted for the appropriate 7. The engine owner will not be charged for diagnostic labor 1) Fuel Injectors
warranty period in the above table. If the part fails during that is directly associated with diagnosis of a defective, 2) Fuel Pressure Regulator
the period of warranty coverage, the part will be repaired or emission related warranted part, provided that such 3) Manifold Absolute Pressure Sensor
replaced by Marine Power at a warranty station. Any such diagnostic work is performed at a warranty station. 4) Throttle Position Sensor
part repaired or replaced under warranty will be warranted
4 www.MarinePowerUSA.com
 1. Introduction
5) Throttle Body 3) Vacuum, Temperature, Check and Timer Sensitive overheating, excessive back pressure, incorrect ignition
6) Coolant Temperature Sensor Valves and Switches timing, excessive total timing.
7) Oxygen Sensors 4) Electronic Controls F) Reimbursement for: Haul-out, launch, towing, storage
8) Intake Valves 13. The repair or replacement of any warranted part otherwise charges, rental charges of any type, inconvenience of
B) Air Induction System eligible for coverage under this warranty may be denied any type, loss of time or income, expense of returning a
1) Intake Manifold from such warranty coverage if Marine Power demonstrates Marine Power product to a service facility, towing, lodg-
2) Air Filter/Flame Arrestor that the engine and/or part has been abused, neglected, or ing, loss or damage to personal property.
improperly maintained, and that such abuse, neglect, or
C) Ignition System G) Carburetor replacement and labor is limited to mechani-
1) Spark Plugs improper maintenance was the direct cause of the need for cal defects only. Replacement does not extend to contam-
repair or replacement of the part.
2) Electronic Ignition System inated fuel, varnish or other residues, changes in fuel
3) Spark Advance/Retard System 14. This Warranty will not apply to: mixtures, poor octane fuel or adjustments beyond five (5)
4) Ignition Coil and/or Control Module hours of engine operation.
A) Use of an accessories or parts not manufactured or sold by
5) Ignition Wires Marine Power. 15. Marine Power reserves the right to limit warranty coverage
D) Lubrication System on engines that have accumulated excessive hours through
B) Neglect, failure to follow maintenance schedules,
1) Oil Pump and Internal Parts commercial use or any other non-typical operation.
accident, abnormal operations, misuse, negligence,
E) Positive Crankcase Ventilation (PCV) System improperly maintained, improperly operated or Special Applications Warranty
1) PCV Valve installed, racing or engine modification. Problems
2) Oil Filler Cap arising from installation, application, exhaust to engine, Marine Power Engines that are used in inboard mud boat
fuel lines to the engine, propping, cooling to the engine applications (“Special Applications”) carry a strict limited war-
F) Exhaust System ranty. The warranty period applicable to Special Applications
or engine damage due to defective electrical hookups.
1) Exhaust Manifolds and Risers such as inboard mud boat usage, shall carry a limited warranty
2) Exhaust Valves C) Rust, corrosion or effects of weather. period of one (1) year or 150 hours, whichever occurs first. This
3) Catalysts warranty shall only cover and be strictly limited to the repair or
D) Water ingestion through exhaust or intake system.
G) Miscellaneous Items Used in Above Systems replacement of parts located from the flywheel forward. Repair
E) Detonation or operation with fuels, oils or lubri- or replacement of drive plates are specifically not covered. Any
1) Hoses, Clamps, Fittings, Tubing, Sealing Gaskets cants which are not suitable for use with this product. and all transmission warranties must be handled by the transmis-
or Devices and Mounting Hardware Detonation causes: Poor fuel quality, overloading of sion manufacturer directly. Marine Power’s emission warranty
2) Pulleys, Belts and Idlers engine, improper gear or propeller selection, engine shall not be limited by these specific limitations. This warranty

www.MarinePowerUSA.com 5
 1. Introduction
covers engine related defective material and/or workmanship 2. Damages caused by extreme temperatures in the exhaust
only, and not replacement or refund of the equipment to which system, including, but not limited to any occurrences of fire,

DANGER
the engine may be mounted.
This Special Applications Warranty shall NOT apply to nor shall it
etc.;
3. Damages caused by or are the result of any sudden impact to
extend to repairs required because of the following: the propeller or any other part of the engine or its accesso-
ries;
1. Damages caused by failures or inadequacies in the cooling
system; 4. Damages or failure of the damper drive plate.
WARNING
2. Safe Boating
tions of the exhaust system are conducted and maintenance is properly

CAUTION performed by a qualified technician. Adequate air circulation in all

areas of your boat are necessary in order to prevent build-up of carbon
monoxide. Please contact your boat manufacturer if you have questions
Carbon Monoxide Exposure
regarding these hazards.
Carbon Monoxide is a odorless, colorless and tasteless gas that cannot be
smelled, seen or tasted. For more information regarding safe boating practices, and/or carbon
monoxide poisoning on recreational boats, contact the following:
Sustained exposure to carbon monoxide gas may lead to brain damage,
unconsciousness or death. National Marine Manufacturers Association (NMMA)
200 East Randolph Drive, Suite 5100, Chicago, IL 60601
Carbon Monoxide is a hazardous gas that is produced when items 312-946-6200 • www.nmma.org
containing carbon are burned. Items such as, but not limited to; wood, coal, United States Coast Guard
gasoline, natural gas, propane or oil. Carbon Monoxide (CO) is found Office of Boating Safety Chicago, IL - CG Headquarters G-OPB-3
in many areas such as any type of internal combustion engines, heat- 2100 Second Street, SW, Washington, DC 20593
ers, charcoal grills, cooking ranges and any other open flame applianc- 202-267-0984 • www.uscgboating.org
es. There are many possible variables for the accumulation of carbon
monoxide. Wind direction, boat speed, vessel proximity to other vessels or American Boat & Yacht Council, Inc. (ABYC)
structures are just a few of the possible variables that would permit 3069 Solomons Island Road, Edgewater, MD 21037-1416
exposure to carbon monoxide gases. It is important that regular inspec- 410-956-1050 • www.abyc.com

6 www.MarinePowerUSA.com
 3. Engine Identification
Every Marine Power Engine is equipped with an Engine Identifi-
cation Tag, also known as a Serial Number Tag. This tag contains
information (model number and serial number) that will be
required before any warranty work (if necessary) can be done.

Airpac: Winterization procedures.

Engines configured for airboat applications. These engines use
closed cooling systems with automotive style radiators. Their
Towpac:
Engines configured for watersport tow boat applications. Engines
exhaust manifolds are dry and usually supplied by the boat
may be configured for conventional inboard or v-drive applica-
builder.
tion. In many of these applications throttle and shift is highly
Enpac: integrated with the boat instrumentation
Engines configured for stern drive (I/O) applications. Cooling
water supply differs depending on the stern drive model mated
Sportpac:
Engines configured for traditional inboard vessels. Many of these
to. See Section 12: Installation Instructions.
applications are twin installations.
Jetpac:
Engines configured for inboard jet drive applications. Cooling
water normally supplied by jet drive. Routing of inlet out out-
let cooling water lines will affect winterization. See Section 9:
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 3. Engine Identification
5.3 GEN V DI 6.2 GEN V DI 6.2 LT4
Engine Type V8 V8 V8
Repower X X X
Original Equipment X X X
Unique Feature Direct Injection Direct Injection DI Supercharged
Displacement 5.3L/327 CID 6.2L/374 CID 6.2L/374 CID
Bore & Stroke 96 x 92 mm 103.25 x 92 mm 103.25 x 92 mm
Compression Ratio 11 : 1 11 : 1 10 : 1
Cylinder Block Aluminum Aluminum Aluminum
Cylinder Head Aluminum Aluminum Aluminum
Recommended Fuel 87 Octane 87 Octane 93 Octane
Max RPM @ Wot 5600 5600 5600
Idle RPM ECM Controlled ECM Controlled ECM Controlled
HP Fuel Pressure 60 PSI 60 PSI 72 PSI
LP Fuel Pressure 4-7 PSI 4-7 PSI 4-7 PSI
Oil Pressure @ 2000 RPM 30-60 PSI 30-60 PSI 30-60 PSI
Min Oil Pressure @ Idle 10 PSI 10 PSI 10 PSI
Operating Temp RW Cooled N/A N/A N/A
Operating Temp FW Cooled 175° F 170°-190° F 170°-190° F
Sparkplug Type 12622441 12622441 12642722
Sparkplug Gap .040” .040” .040”
Timing @ Idle ECM Controlled ECM Controlled ECM Controlled
Timing @ 4000 RPM ECM Controlled ECM Controlled ECM Controlled
Firing Order 1-8-7-2-6-5-4-3 1-8-7-2-6-5-4-3 1-8-7-2-6-5-4-3
Alternator Rating 150 amps 150 amps 250 amps
Crankcase Oil Dexos 15W50 GEN 2 Dexos 15W50 GEN 2 Dexos 15W50 GEN 2
Oil Capacity 8 Qts. 8 Qts. 8 Qts.

Closed Cooling Fluid Antifreeze/Water Antifreeze/Water Antifreeze/Water

Closed Cooling Capacity 10 Qts. 10 Qts. 10 Qts.

8 www.MarinePowerUSA.com
 4. Electronic Sequential Fuel Injection Information
The engines covered in this manual are equipped with • Engine Coolant Temperature (ECT) Sensor Engines may include one or more of the following optional
Electronic Sequential Fuel Injection. The main fuel system sensors.
• Engine Oil Pressure Sensor
components include: • Engine Oil Temperature Sensor
• Manifold Absolute Pressure (MAP) Sensor
• The electric high and low pressure fuel pumps • Fuel Pressure Sensor
• Knock Sensor
• The throttle body assembly • Transmission Oil Temperature Sensor
• Camshaft Positioning (CMP) Sensor
• The fuel injectors • Exhaust Manifold Temperature Sensor
• Crankshaft Positioning (CKP) Sensor
The fuel injection system is controlled by an Electronic Control • Barometric Pressure (BARO) Sensor
Module (ECM). The ECM continually monitors information from • Intake Air Temperature (IAT) Sensor (combined with the
the various sensors on the engine and configures the spark MAP sensor on the 5.7) • Super Charger Inlet Pressure (SCIP) Sensor
timing and fuel delivery for optimum performance. Additionally, • Throttle Position (TPS) Sensor
the ECM protects the engine from over-revving and monitors the
oil pressure and water temperature. • Pedal Position (PPS) Sensor

The following sensors constantly provide information to the • Pre-Catalyst O2 (O2) Sensor (Catalyst equipped engines)
ECM. • Post-Catalyst O2 (O2) Sensor (Catalyst equipped engines)

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 5. Engine Alarms and Instrumentation
Digital Alarms If the “MIL” lights and/or the “buzzer” sounds during opera-
tion, the operator should scan the instrument panel readings for
If, for any reason, one or more of these sensors or associated
possible sources of trouble. Conditions that may cause alarm ac-
wiring malfunctions, the ECM’s built in self-diagnostic system sets
tivation include:
a trouble code and turns on the Malfunction Indicator Light (MIL)
or sounds a buzzer to alert the operator of a malfunction. • Low Oil Pressure
The MIL, buzzer and gauges can signal that something is wrong • Engine Overheat (High Temperature)
before it becomes serious enough to cause an expensive repair. • Electronic Throttle Malfunction
Paying attention to the MIL, buzzer and gauges could also save
you or others from injury. The MIL may be replaced by verbiage • Engine Misfire
such as “Service Required” on boats equipped with electronic See Section 11: Engine Diagnostics and Codes for more
instrumentation. information.
The MIL or “Service Required” notice comes on when there is a If the boat is equipped with CAN-Buss Messaging (Electronic
problem with an engine function. Gauges can also indicate when Instrumentation), the main screen will likely display a “Service
there is a problem with an engine functions. Often gauges and the Required” message when the ECM records an active trouble code.
MIL (Service Required) work together to let you know that there is
IMPORTANT: A failure with the Electronic Throttle will result in
a problem with your engine.
idle only operation of the engine. In some cases, the throttle may
In most cases, when the “MIL” is on, the engine(s) may lose some be reset by turning the key off and then restarting the engine.
performance and/or efficiency, but remain running adequately. The operator should contact his servicing dealer to determine the
Also, the light may go out or become intermittent, but a trouble exact cause of the failure.
code will be logged for future diagnosis. In any case, the operator
must obtain service by an authorized dealer to determine and
repair the exact cause of the malfunction.
The engine ECM is programmed to control the engine alarm
system. This system is configured to turn on an instrument
panel mounted indicator (“MIL” or “Check Engine”) light, and,
optionally, an audible (“buzzer”) alarm to warn the operator of
engine problems.

10 www.MarinePowerUSA.com
 5. Engine Alarms and Instrumentation
Instrumentation IMPORTANT: Engines are designed to use
Boat builders use many different types of instrumentation in their both buzzers and MIL lamps. Buzzers are
boats. The operator should understand his instrumentation and use to alert operators of severe problems,
note any abnormal operating conditions. such as: Low oil pressure, high engine
temperature or low fuel pressure. See Section
11: Engine Diagnostics and Codes for more
information.

Analog Instrumentation

Canbus Instrumentation

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 6. SSVEC Fuse and Relay Enclosure

All relays and fuses are located in the Severe Service Vessel
Electrical Center (SSVEC). This enclosure is capable of withstand-
ing direct water spray. Additionally, it contains a Goretex vent
which allows humid vapors to escape without allowing water in.

12 www.MarinePowerUSA.com
 6. SSVEC Fuse and Relay Enclosure

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 6. SSVEC Fuse and Relay Enclosure

14 www.MarinePowerUSA.com
 6. SSVEC Fuse and Relay Enclosure

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 7. Precautions
Oil Level Hydrolock To remove water from engine cylinders, take the following steps:
Check the oil level before each engine start up and every eight Hydrolock describes a condition in which water enters the cylinder 1. Remove all spark plugs.
(8) hours of continuous operation. It should be understood that of an engine. Water is not compressible and can cause catastroph- 2. Remove coil wire.
internal combustion engines will use a certain amount of oil ic damage. Do not try to start an engine that shows sign of having
during operation as a cooling and lubricating agent (especially water in the cylinders. Beware of these situations: 3. Crank engine for 15 seconds.
during break-in period). Oil consumption should decrease after 4. If there are any abnormal sounds STOP ENGINE immediate-
1. Following Wakes: Sudden slow-downs may cause the boat
approximately 100 hours of operation. ly and contact your Marine Power dealer.
wake to flow over the transom of your boat.
IMPORTANT: The space between the “FULL” and “ADD” marks 5. Change engine oil and filters.
2. Engine Shutdown: Sudden engine shutdown while the boat
on the dipstick represent one quart. It is not necessary to add oil is moving may force water into the exhaust system. 6. Replace spark plugs and reattach coil wire.
unless the level is at or below the “ADD” mark.
3. Improper Installation: Refer to Section 13: Exhaust Piping. 7. Start engine. If there are any abnormal sounds STOP
Engine dipstick level may change due to the angle of An exhaust system without flappers and the specified incline ENGINE immediately and contact your Marine Power dealer.
installation. Ensure that “high” oil level is properly marked increases the likelihood of water entering the engine.
accordingly. 4. Improper Hoisting: Operators are sometimes tempted to
reduce hoisting time for propeller changes by hoisting only
When adding crankcase oil, DO NOT OVERFILL. the boat stern. Such hoisting can cause residual water in the
If crankcase is overfilled, it will cause foaming or aeration of exhaust system to enter engine cylinders. Water entering
oil in the oil pan. This will effect oil pressure which may result engine cylinders will cause the engine to lock because water
in severe internal engine damage. does not compress.
5. Poor engine cover design: Engines are supposed to be pro-
tected from top side water. If the engine hatch (cover) allows
water to spill on to the top of the engine, water may enter
the cylinders through the flame arrestor.
6. Belt Slinging: Too much water in the bilge of a boat will
sometimes be picked up by the crankshaft pulley and car-
ried into the flame arrestor during a hard acceleration
maneuverer.

16 www.MarinePowerUSA.com
 8. Engine Operating Instructions
Gasoline Requirements Oil Requirements If this is the initial start on a new engine turn the ignition
(key) switch to the on (run) position (first detent on key switch)
Marine Power calibrates their engines EXCEPT LT4 for use with Marine Power recommends the following:
and wait for 10 seconds. Turn the ignition off and repeat this
high quality lead-free gasoline with a minimum octane rating of Engine Brand/Weight procedure 2-3 times or until you hear the fuel pump prime. Then
87. Additionally, Marine Power uses octane scaling calibrations
4.3L Dexos 15W-30 GEN 2 turn the key to the start (crank) position (2nd detent). It is not
where applicable. Octane scaling enables the engine to “learn
5.3L Dexos 15W-30 GEN 2 necessary to hold the key switch in this position as the Marine
up” if a higher octane fuel (such as 92) is purchased. There is a
6.2L Dexos 15W-30 GEN 2 Power “SMART START” will take over. If the fuel pump is primed
noticeable performance difference with higher octane fuels. If the
LT4 Dexos 15W-30 GEN 2 the engine should start within 3-5 seconds. After the engine starts,
boat is used in heavily loaded conditions (i.e. heavily ballasted to
idle speed (RPM) will be controlled by the ECM. The idle RPM will
produce large wakes for surfing or wakeboarding) Marine Power Marine Power recommends that the engine oil be changed ev- be elevated following a cold start until the engine warms to its
recommends the use of premium fuel (93 octane minimum). See ery 100 hours of engine operation, but no less frequently than normal operating temperature.
LT4 Warning. once each calendar year, and that the engine oil filter be replaced
every time the engine oil is changed. Check for water flowing through the engine cooling
The use of gasoline containing ethanol is very prevalent. Marine
system. Water should mix with the engine exhaust. In all cases,

DANGER
Power engines are calibrated to operate on fuel containing up to
Starting Engine EFI your positive indicator is exhaust water flow.
10% ethanol (E10). Do not use fuel with ethanol content higher
than 10% (E10). DO NOT operate engine without water being supplied Check the boat’s instrument panel for any service warnings or
to raw water pump as pump impeller and engine will alarms.
Ethanol blended fuel acts as a solvent and will absorb moisture.
be damaged. Check operation of throttle and shift controls.
Excessive moisture can cause lean conditions, vapor lock and
shortened fuel life. The solvent characteristic can cause gum,
WARNING
Check fuel tank fill level before leaving the trailer or dock.
sludge and other particles to be loosened up and carried through
the fuel system. Engine Break-In/25 Hour Inspection
Gasoline vapors are highly explosive under certain conditions.
Marine Power recommends the use of fuel stabilizer such as To insure the maximum life of your Marine Power Engine, the
Sta-Bil. Fuel stabilizer is recommended for winter storage and following engine break-in guidelines are recommended.
should also be used if you expect to use less than a full tank of Operate the bilge blower for five (5) minutes. If not equipped
Marine Power considers the first ten (10) hours of engine
fuel over a 2-3 week period of time. Follow the label instructions
whenever adding fuel stabilizer to the fuel tank. CAUTION
with a bilge blower, open engine hatch and leave open before
starting the engine to remove any explosive vapors from the
operation to be the break-in period.
During this break-in period:
engine compartment.
Place shift lever in the neutral position. Do not operate the engine at wide-open throttle.

www.MarinePowerUSA.com 17
 DANGER
8. Engine Operating Instructions
Do not operate the boat at or near the maximum capacity
specified on the USCG label.
Limit the maximum engine speed to 3500 RPM
WARNING
The LT4 Is a Premium 93 Octane REQUIRED engine. The engine will
Avoid running the engine at a constant/steady RPM for sustained operate at significantly reduced power output with octane levels
periods of time. (i.e. vary the throttle/engine speed frequently) down to 90. Operating the LT4 on fuel below 90 Octane can result

CAUTION
in engine damage and or failure! Such failure will not be covered
Check the engine oil level at the beginning of each boating day,
under warranty!
and after each 2-3 hours of engine operation. Any time oil level
is checked look for milky discoloration, if found consult with your
dealer.
After the first ten (10) hours of engine operation but before
twenty-five (25) hours return the boat to your dealer for its first
engine oil and filter change and initial engine inspection.

18 www.MarinePowerUSA.com
 9. Winterization
Full Closed Cooled Engines
Test antifreeze-water concentration to assure adequate protection
for your location.
Remove hoses from inlet and outlet of crankshaft seawater pump.
Remove drain plug from transmission/engine oil cooler.
Remove drain plugs (if equipped) from exhaust risers.
Note the routing of your inlet cooling water hose to make sure
there are no locations which may trap water. If your engine is
attached to a v-drive transmission, pay particular attention to the
draining of the v-drive cooler.
Remove end caps on heat exchanger. Inspect for debris and
trapped water. Remove zinc anode and replace if necessary.
Spray each of your engine mounts with WD-40 or equivalent
lubricate.

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 9. Winterization
LT4 Water Flow Full Closed Inboard Jet Engines
Orange represents coolant flow
Test antifreeze-water concentration to assure adequate protection
Green represents raw water flow
for your location.
These engines are designed to be self-draining, however, it is
recommended that the heat exchanger ends be inspected for de-
bris and trapped water frequently.

6.2 Jetpac
For best results use a Vacuum Cooling System Filler when
refilling or bleeding engine coolant.

20 www.MarinePowerUSA.com
 10. Engine Maintenance
Scheduled Maintenance By Owner
Service Engine After Every 50 Every 100
Startup 10 Hours of Hours of Hours of
Each Day Operation Operation Operation
Check Engine Oil Level * 3 3
Inspect Fuel Lines and Connections for Leaks 3 3
Check Coolant Level in Tank (If Equipped with Closed Cooling) 3 3
Inspect and Clean Sea Strainer (If Equipped) 3 3
Inspect Entire Power Package for Leaks (Water, Fuel, Oil, Exhaust, etc.) 3 3
Inspect Belts for Tension and Wear 3 3
Inspect Battery (Terminals and Fluid Levels) 3 3
Check Battery Connection to Engine 3 3
Touch Up Exterior Surface with Marine Power Paint 3 3
Inspect Zinc Anodes in Heat Exchanger for Deterioration (If Equipped with Closed Cooling) 3 3
Check Power Steering Fluid (If Equipped) 3
Check Transmission Fluid Level 3 3
Lubricate Starter Pinion and Shaft 3
* Engine Start-Up Each Day and Once Every Eight (8) Hours of Operation.

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 10. Engine Maintenance
Scheduled Maintenance By Qualified Technician
Service Engine After Every 50 Every 100
Startup 10 Hours of Hours of Hours of
Each Day Operation Operation Operation
Change Engine Oil and Filters 3 3 3
Change Filter on Fuel/Water Separator 3 3
Check Engine Mounts (Tightness) 3 3
Check Riser and Manifold Bolts for Tightness 3 3 3
Check for Loose, Damaged or Missing Engine Parts 3
Check Wire Harness Plugs for Corrosion and Connections 3
Check Condition of Spark Plugs (Replace if Necessary) 3
Inspect Hoses for Deterioration 3
Replace Impeller in Seawater Pump 3
Check Propeller and Shaft Alignment 3
Clean and Inspect Flame Arrestor and Crank Case Vent Hose 3
Change Transmission Fluid 3
Change Coolant (If Equipped with Closed Cooling) 3
Clean Sea Water Section of Heat Exchanger 3

22 www.MarinePowerUSA.com
 10. Engine Maintenance
This manual provides basic information on routine maintenance Electrical, ignition and fuel system components on Marine Power Crankcase Oil Change
of Marine Power Engines. Whether the reader is an experienced Engines comply with U.S. Coast Guard (USCG) Rules and Regula-
IMPORTANT! Start engine and operate until normal temperature
marine mechanic or a first time boat owner, we strongly suggest tions to minimize risks of fire and explosion. Use of replacement
is reached. Warm oil flows more freely carrying away more im-
you thoroughly read these procedures BEFORE you attempt any electrical, ignition and fuel components which do not comply with
purities. Remove the oil into a suitable container. Marine Power
procedure. Make sure you are familiar with the tools suggested these rules and regulations could result in a fire or explosion and

DANGER
equips their engines with an E-Z oil drain hose. This hose can
and the methods recommended. Safety is our first concern. If must be avoided. The electrical and ignition system is capable of
sometimes be routed through the hull drain fitting while the boat
repair required is beyond your expertise, please contact your violent electrical shock. Always disconnect the battery cables when
is on its trailer. Draining can take several hours if the oil is not
dealer or other qualified technician. This manual contains guide- performing any work where the cables could touch.
warmed before draining. Some oil will remain in the pan and en-
lines to convey a particular level of risk:

DANGER
Take care to properly install and tighten all components when gine. It is a small quantity but may make the new oil appear used.

DANGER
servicing the electrical, ignition and fuel systems. If the installa-

Hazards that will result in severe injury or death.

tion is not correct, sparks could ignite fuel vapors from the fuel
system. WARNING
If you are doing repair work around the intake or exhaust The Federal Water Pollution Control Act prohibits the discharge of
openings, always protect those openings against foreign oil or oily waste into or upon the navigable waters and contiguous
WARNING
WARNING
matter entering the cylinders. Care must be taken to use zone of the United States, if such discharge causes a film upon, or

CAUTION
exact replacement parts. Damage could result if mismatched. discoloration of, the surface of the water, or causes an emulsion or
Hazards that could result in severe injury or death. Caution: If a grade 5 hex head bolt is removed, the same grade 5, sludge beneath the surface of the water. Violators are subject to a
Hazards which could result in minor injury or property damage. hex head bolt must be replaced. If you cannot re-use the penalty of $5,000.00.
Please be careful. same bolt, do not improvise. Performance could be sacrifice
After replacing drained oil, start engine and run for 5 minutes to
CAUTION
without original Marine Power parts or parts recommended
circulate oil throughout. Inspect entire engine for leakage. Shut
CAUTION
by Marine Power. A marine environment is a tough one. Parts
subjected to salt water can rapidly corrode and engine failure off engine and wait 5 minutes for oil to drain back into pan. Check
could result. Warranty on Marine Power Engines could also be level with dipstick. Add oil to proper level if needed.
affected if other than recommended replacement parts are used.

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 WARNING
10. Engine Maintenance
Start engine. Run for approximately 5 minutes and inspect for
CAUTION leaks.
Shut off engine and wait 5 minutes for oil to drain back into pan.
DO NOT overfill crankcase with oil. Agitation or splashing of oil may
cause it to become aerated, which will affect oil pressure and may Check level with dipstick. Add oil to proper level if needed.
result internal engine damage from lack of lubrication. Oil being ALWAYS CONTACT YOUR NEAREST MARINE POWER
splashed by reciprocating engine parts onto the walls of the cylinder SERVICING DEALER IF YOU HAVE A PROBLEM.
in greater quantity than the rings can control will subsequently be
drawn into the combustion chamber and burned. Continuous oper-
ation under these conditions can cause carbon to form on chamber
surfaces, which will adversely affect engine performance and may
lead to premature engine repair.

Oil Filters
NOTE: Lay a towel or catch basin under the filter(s) to catch any
spilled oil.
Unscrew old filter by using an oil filter wrench and turn count-
er clockwise. Once removed, clean mounting base. Be sure old
gasket is removed from mounting base.
Apply thin film of oil (do not use grease) to filter gasket. Be sure
gasket is seated properly in base of oil filter.
Hand tighten filter, plus ½ turn, after gasket contacts mounting
base. Use a filter wrench is necessary. Do not over tighten.
Check to see that oil shows “FULL” on dipstick.
Start engine. Turn on water. Run for approximately 5 minutes and
inspect for leaks.
Check to see that oil shows “FULL” on dipstick.

24 www.MarinePowerUSA.com
 10. Engine Maintenance Not used on LT4
Flame Arrestor
Fuel Flow Schematic
Clean the flame arrestor regularly.
Low Pressure Feed Pump is 4-7 PSI at outlet. High Pressure Feed Pump
1. Remove fastener from flame arrestor. Outlet (60 PSI)
Inlet has a small screen inside fitting. This screen
2. Clean with a suitable solvent and blow dry. may be flushed by reversing polarity on electrical
3. Reverse steps to assemble. connectors and operating pump in reverse. High
pressure Feed Pump must be unplugged during this
G-Force Fuel System procedure.
1. Position catch basin under filter.
2. Remove cooling cover.
3. Unscrew canister bowl.
Low Pressure
4. Pull element down from pump. Feed Pump
5. Push new element (Part #396007) on pump until click is
felt. IN OUT
Fuel Filter
6. Replace O-ring (included with filter).
7. Re-install canister bowl on unit - snug tight only.
8. Two 10-second key ups should prime system.

Negative Positive
Terminal Terminal

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 DANGER DANGER
10. Engine Maintenance
Battery Cables Alternator Belt Tension

WARNING WARNING
Do not recharge a weak battery in a boat. Remove and recharge Make sure ignition key is removed and engine is not running before
in a ventilated area away from fuel vapors, sparks or fames. inspecting belts.
Electrical systems in a marine environment require periodic
Serpentine belt system maintains tension with a spring-loaded
CAUTION CAUTION
attention. Continued use of a weak battery or dirty terminals can
cause solenoid or starter problems. Clean battery and terminals tensioner. Normally, no maintenance is required. Exploded View of Sea

DANGER
every 100 hours. Note the condition of your battery cables. When
reconnecting battery cables make sure that the RED cable is on
Sea Water Pump Impeller Replacement
Water Pump

the (+) terminal and the BLACK cable is on the (-) terminal. Black Remove 4 screws from pump cover.
is ground. Remove cover and gasket.
Pry out impeller using a flat screw driver on each side of the
WARNING center of the shaft.
Install new impeller.
Do not run AC wiring adjacent to DC wiring.
Replace gasket, cover and re-tighten screws.
Multiple Engine
Battery Precautions - EFI
CAUTION
In multi-EFI power packages, each engine must be connected to
its own battery. This provides the required voltage source for the
ECM. In these applications where battery switches are used, it is
important that each switch be positioned to allow each engine to
run off its own individual battery. DO NOT run engines with the
battery switches in “BOTH” or “ALL” positions. This will allow the
other engine’s battery to be used in case of emergency to start the
engine with the dead battery.

26 www.MarinePowerUSA.com
 10. Engine Maintenance
Closed Cooling System el in the surge tank at all times. If coolant is consistently low, until thermostat is open and all air purged. Once thermostat is
additional inspection for leaks in the cooling system may be open and engine temperature is stable, reinstall surge tank cap.
The closed cooling system is designed to provide extended life
required.
to your new Marine Power engine. Your engine will operate at
a different temperature range from a raw water cooled engine. Filler Neck and Pressure Cap: DO NOT remove
Please refer to the appropriate Engine Identification on Page pressure cap when engine is HOT. If coolant is low, add the proper
8 for proper cooling ranges. The cooling system does require mixture (50% water/50% antifreeze) to the top of the filler neck
certain preventative maintenance to keep it in optimum operat-
ing conditions. DANGER
located on the heat exchanger tank. If coolant is consistently low,
additional inspection for leaks in the cooling system may be
required.
Heat Exchanger: All closed cooled engines incorporate a shell
and tube heat exchanger. This unit exchanges heat between Filling Closed Cooling System
the sea water and the engine coolant. These units require very
little maintenance. A routine inspection of the inter or tube sheets
during winterization is sufficient. Be sure to remove any debris WARNING
found during this inspection. Do not remove pressure cap when engine is hot. Coolant is
Zinc Anode: Your heat exchanger is equipped with a zinc under pressure and may be forced out causing personal injury. After
anode that is approximately 2” long. If your engine is operated engine is cooled, remove cap slowly to allow pressure to escape.
and maintained in saltwater this anode should be inspected for
deterioration after the first 10 hours of operation. Inspect again
after 50 hours of operation and every 50 hours thereafter.
CAUTION
IMPORTANT! The closed cooling system must remain filled
year-round with the proper mixture of 50% antifreeze/50%
water to assure protection of system during the lowest exposed
Recovery Bottle: The plastic recovery bottle is attached to the temperatures. Insure that all drain plugs are installed and
heat exchanger tank (on most models) and fills with coolant tightened. Fill heat exchanger (tank) with 50/50 antifreeze/water
during operation when the internal water temperature is higher. mixture. After initial fill, start engine and continue filling heat
If necessary, add coolant only when engine is cold. exchanger. Engine must be purged of air by bleeding system.
Surge Tank: Some models are equipped with a surge tank 4.3/5.3/6.2L Horizontal Heat Exchanger Full Systems:
rather than a recovery bottle. The surge tank replaces the heat These engines maybe difficult to purge without a vacuum
exchanger filler neck and pressure cap and is pressure capable assembly. If such an assembly is not available, operator should
whereas the recovery bottle is not. Maintain the appropriate lev- continue to leave surge tank cap off and force coolant into bottle

www.MarinePowerUSA.com 27
 11. Engine Diagnostics and Codes
Name Description Trouble MIL Buzzer Reduce Comments
Code Lamp RPM
Barometric Sensor Sensor alerts ECM if barometric measurement is to high or to low. 108 X
Boost Bypass 66034
Boost Control ECM detects either an over boost or problem with circuit. 66035 X X Only applies to supercharged engines.
Buzzer Driver 66007
Call Memory 630
Cam Phaser (W) ECM sets code if sensor fails diagnostic test. 65570-73 X X Limits RPM to 4000. Often caused by high or low engine oil level.
Cam Sensor (W) ECM sets code if sensor fails diagnostic test. 65723-26 X
Cam Gov Message ECM sets code if specific OEM controller message is lost. 65560 X Normally only applies to tow sport applications.
Cam Bus Hardware (1) ECM sets code when it detects problem with can bus circuit. 65558-59 X
Cam Bus Stbl Cntrl Message ECM sets code when it detects problem with can bus circuit. 65557 X
Catalyst Efficiency Test ECM detects failed catalyst efficiency test. 65675-76 X 75 indicates odd bank, 76 even bank.
Change Oil Now/Soon 65555
Coolant Temp Sensor Sensor fails diagnostic test. 110 X
Coolant Temp Warning Sensor alerts ECM if coolant temperature is above 220° F. 110 X Code clears at 95° F. Reduces RPM to 2500.
Coolant Temp Warning Extreme Sensor alerts ECM if coolant temperature is above 239° F. 110 X X X Code clears at 220° F. Reduces RPM to 2500.
CPU 65580
Crank Sensor ECM sets code if sensor fails diagnostic test. 636 X Typically won’t start if code is triggered. Check tightness of
sensor and electrical connections.
Dev Mode Cal 65730
Diagnostic Trouble Code Lamp (1) 66008
Diagnostic Trouble Code Lamp (2) 66009
Diagnostic Trouble Code Lamp (3) 66006
Exhaust Gas Recirculation (EGR) 66016

28 www.MarinePowerUSA.com
 11. Engine Diagnostics and Codes
Name Description Trouble MIL Buzzer Reduce Comments
Code Lamp RPM
Emergency Stop Warning 65710
Electronic Spark Timing Circuit (EST) ECM sets code if ignition coil fails diagnostic test. 65541-48 X Last digit corresponds to coil number.
Electronic Throttle Control ECM sets code if dual sensors out of range. 65604-05 X X Limits RPM to 1000. Check pedal adjustment.
Electronic Throttle Control ECM sets code if dual sensors do not agree. 65613 X X Limits RPM to 1000. Pedal may need replacement.
Electronic Throttle Control ECM sets code if it detects throttle body issues. 65615 X X Limits RPM to 1000. Check for stuck throttle body blade.
Electronic Throttle Control 65618
Electronic Throttle Control 65600
Electronic Throttle Control 65601-02
Electronic Throttle Control 65610
Fuel Pressure Sensor Sensor fails diagnostic test. 94 X
Fuel Pressure Error Sensor alerts ECM if fuel pressure is too high or to low. 94 X X Check or replace filters. If problem persists then further
diagnostics needed. Reduces RPM to 2500.
Fuel Pump Relay 1 ECM detects abnormal relay current or voltage. 66017 X
Fuel Pump Relay 2 ECM detects abnormal relay current or voltage. 66025 X
Fuel Level Sensor 1 96
Fuel Level Sensor 2 38
Fuel Rail Pressure Diag Sensor 1349
Fuel Rail Pressure Sensor 157
Fuel Rail Sent Message 66032
Gear Temp Sensor alerts ECM if gear oil temperature is above 300° F. 174 X X Not normally used in jet or repower applications. Used for Towboats.
General Warning 65701-03
Gov Status Lamp 66005
Hpfp Press Error 66031

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 11. Engine Diagnostics and Codes
Name Description Trouble MIL Buzzer Reduce Comments
Code Lamp RPM
Hpfp Solenoid 66029
Hpfp Solenoid Enable 66028
Inj 66051-58
Inj Enable 651-58
Inter Cooler Replay ECM detects abnormal relay current or voltage. 66030 X Only applicable on supercharged engines. Driver controls
intercooler pump relay.
Knock Excessive 65550
Knock Sensor ECM sets code if sensor fails diagnostic test. 65551-52 X 51 indicates odd side. 52 even side. Cooler pump relay.
Manifold Absolute Pressure ECM sets code if sensor fails diagnostic test. 106 X
Manifold Air Temperature Sensor ECM sets code if sensor fails diagnostic test. 105 X Not all engines are equipped with this sensor.
Manifold Air Temperature Warning Sensor alerts ECM if inlet air temperature is too high. 105 X X On supercharged engines check intercooler system. Reduces
RPM to 2500.
Main Health Coprocessor ECM problem. 65581 X Check the memory power, the main power and the ground on
ECM. May need replacement.
Malfunction Indicator Lamp Driver ECM sets code if driver fails diagnostic test. 66003 X Boat may not be equipped with MIL light.
Misfire ECM detects cylinder misfire. 65590-99 X Last digit corresponds to cylinder number. 99 is random cylinder misfire.
Electronic Throttle Control (ETC) 51
Non-Volatile Random Access Memory 65582
OEM Output 66040-43
OEM Signal Lamp 66060-63
Oil Level Warning 98
Oil Pressure Sensor ECM sets code if sensor fails diagnostic test. 100 X
Oil Pressure Warning Sensor alerts ECM if oil pressure is too high or low. 100 X X Reduces RPM to 2500.
Oil Temperature Sensor ECM sets code if sensor fails diagnostic test. 175 X

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 11. Engine Diagnostics and Codes
Name Description Trouble MIL Buzzer Reduce Comments
Code Lamp RPM
Oil Temperature Warning Sensor alerts ECM if engine oil temperature is above 300° F. 175 X X Reduces RPM to 2500. Not used on 5.7 Engines.
Oxy Fuel Trim ECM sets code after detecting abnormally rich or lean condition. 65565-66 X 65 indicates odd bank, 66 even bank.
Oxy Heater ECM sets code after detecting failure in O2 sensor heaters. 66019-22 X 19 = pre-o2 odd bank, 20 = pre-o2 even bank, 21 = post-o2 odd
bank, 22 = post-o2 even bank.
Oxy Response ECM sets code after determining O2 sensor response is slow. 65567-68 X 67 indicates odd bank, 68 even bank.
Oxy Voltage ECM sets code after detecting abnormal voltage at O2 sensors. 65561-64 X 61 = pre-o2 odd bank, 62 = post-o2 odd bank, 63 = pre-o2 even
bank, 64 = post-o2 even bank.
Powertrain Relay ECM detects abnormal relay contact voltage. 66013-14 X
Supercharger Inlet Pressure Sensor Supercharger inlet pressure too high or too low. 3563 X Only applicable on supercharged engines.
Shift Interrupt 66026
Slow Mode Lamp 66010
Speed Based Output 66011
Speed Sensor ECM sets code if speed sensor fails diagnostic test. 84 X Not normally used in jet or repower applications. Used in
Towboat applications.
Starter Relay Driver 66002
SVS Lamp ECM detects issue with SVS circuit. 66004 X This circuit controls the warning buzzer alarm.
System Voltage ECM sets code if system voltage is below 10 or above 16. 627 X Check alternator connections and for tight belt. May need
replacement.
Tachometer 66018
Tiap Sensor 3562
5V Buffer ECM detects out of range voltage on low voltage output pins. 65620-23 X Used to supply voltage to engine sensors. It is a 5 volt reference.
Var Gov 65690

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 11. Engine Diagnostics and Codes
Start Sequence 1 (MEFI 7) “Bussmann” 2-way Connector #5
• Turn Battery Switch on (if boat equipped).
A. Engine Ground
5C Energized with 12 volts B. Not used
with Battery Switch on C. B+ from Starter Post
(Power enters Bussmann) C A
Connector viewed as
connected to the Bussmann
(Wire side view)

Start Sequence 2 “Bussmann” Connector #2 (Grey)

• Turn key to ignition position.
• 12 volts @ 2C enables Run/Crank Relay (R2).
• Run/Crank Relay then energizes 2E which supplies 12 volts to 1. Ignition on Enables Run/Crank
ECM J1-51. A. Ignition+ to Fuel Relay (R2)
Injectors D C B A
• ECM “Wakes Up”.
B. B+
• ECM than provides 12 volts to Bussman 1E and 1F which energizes C. Ignition+ from Helm 2. 2E supplies 12 volts
Fuel Feed Pump Relays. D. Intercooler Pump Relay Control to ECM J1-51. ECM “Wakes Up”
J1-49 E F G H
• Fuel Feed Pump Relays provide 12 volts to 1C and 1G which turns E. Run/Crank Relay to J1-51
on Feed Fuel Pumps for initial prime. Listen for pumps running. F. 12V+ to Intercooler Pump
G. Ignition+ to Ignition Coils
H. Ignition+ to O2 Sensor Heater

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 11. Engine Diagnostics and Codes
“Bussmann” Connector #1 (Black)
A. Auxiliary Relay
B. Auxiliary Relay Control
3. ECM provides 12 volts to 1E C. Fuel Feed Pump 2
and 1F. Energizes Fuel Feed D. Powertrain Relay
Pump Relays Contacts - J1-73
E. J1-44 Fuel Pump 1 Relay Control
D C B A F. J1-50 Fuel Pump2 Relay Control
4. Fuel Pump Relays G. Fuel Feed Pump 1
provide 12 volts at 1C H. Plug
and 1G to Fuel Feed Pumps
E F G H

Start Sequence 3
“Bussmann” Connector #3 (Blue)
• Momentarily turn Key Switch to Start. ECM receives crank request
on pin J2-22. A. B+ to DLC
B. J1-72 Powertrain Relay Control
Start Contact On C. Plug
5. ECM supplies 12 volts to 3F. D. Plug
• ECM pin J1-63 supplies 12 volts to Bussmann 3F which energizes Energizes Starter Relay. E. Plug
Starter Relay. F. J1-63 Starter Relay Control
D C B A G. Ground
• Starter Relay then provides 12 votls to Bussmann 3H which in turn H. Starter Solenoid
energizes Start Solenoid. Engine cranks.
6. 3H provides 12 volts
to Starter Solenoid. Engine
cranks. E F G H

Starter Relay Control: 12 volts + from

ECM in Neutral

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 12. Trouble Shooting
The following trouble shooting hints are not all inclusive, but are the most common found. In all cases, if the cause of the problem is outside your capability to repair or correct, contact your dealer.

Engine Will Not Turn Over

Possible Cause Remedy
Low Battery or Bad Connection Check/Charge/Replace. Requires 12 -14 volts
ECM B+ 18 ga. Wire not Powered Must be Connected Directly to Battery or Battery Switch
Faulty Battery Cable See Table for Proper Size
Blown Fuse Check Fuses in SSEC Box
Faulty Neutral Switch Replace
Bad Starter Solenoid or Motor Replace
Shift Control in Gear Take Out of Gear
Faulty Starter Relay Check Relay in SSEC Box
Hydro Lock Remove Spark Plug. Look for Water in the Cylinder
Engine Emergency. Stop Switch Activated Clear DTC Code

Engine Cranks But Will Not Start

Possible Cause Remedy
Faulty Fuel Pump Note That Low Pressure and High Pumps Are Operating
Insufficient Fuel Supply Check Fuel Supply Shut Off Valve, Check Fuel Filter. 5.7/6.0/6.2L - Requires 60 PSI Fuel Pressure
Insufficient Cranking RPM Check Battery Voltage. Voltage Should Be Over 12 volts
Bad/Old Fuel Replace
Insufficient Fuel Supply Approximately 60 PSI. Fuel Pressure Must Be Adequate at Wide Open Throttle at Full Load
Active Trouble Code See Dealer
Leaky Valves See Dealer
Ensure a tune up is done every 100 hours or every season.

34 www.MarinePowerUSA.com
 12. Trouble Shooting
Engine Runs Poorly at High RPM
Possible Cause Remedy
Low Grade or Old Fuel Check/Clean/Replace
Ignition Timing Only Pertains to HVS (Distributor) on 5.7L. See Dealer
Active Trouble Code See Dealer
Engine Overheating See Engine Overheating on Page 45
Restricted Exhaust Check Exhaust System
Overfilled Crankcase Check Oil Level
Plugged Fuel Tank Vent Check Vent Line for Blockage
Insufficient Fuel Supply Approximately 60 PSI. Fuel Pressure Must Be Adequate at Wide Open Throttle at Full Load
Restricted Anti-Siphon Valve Remove From Fuel Tank and Verify Spring Pressure
Low Compression See Dealer
Engine performance can be greatly affected by boat hull and prop condition.

High Speed Miss

Possible Cause Remedy
Water in Fuel Inspect/Clean/Replace
Clogged Fuel Filter Change Fuel Filter
Insufficient Fuel Supply Approximately 60 PSI. Fuel Pressure Must Be Adequate at Wide Open Throttle at Full Load
Spark Plug or Wires Verify That All Plug Wires Are Attached
Loose Ignition Connection Check That All Connectors Are Attached
Detonation Verify Fuel Pressure and Fuel Quality
NOTE: A Misfire will Cause a Trouble Code and RPM Reduction.

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 12. Trouble Shooting
Fuel System - Rich
Possible Cause Remedy
Dirty/Clogged Flame Arrester Check/Clean/Replace
Malfunctioning Fuel Pressure Regulator Verify That Fuel Pressure Is Not Too High

Fuel System - Lean

Possible Cause Remedy
Empty Fuel Tank Fill Tank
Vapor Lock Ventilate Engine Compartment to Reduce Temperature
Insufficient Fuel Supply Approximately 60 PSI. Fuel Pressure Must Be Adequate at Wide Open Throttle at Full Load

Poor Fuel Economy

Possible Cause Remedy
Boat Hull Dirty Clean/Check/Adjust
Incorrect Prop Size or Damage Verify with Dealer or Manufacturer
Clogged Flame Arrester Check/Clean/Replace
Low Engine Compression See Dealer
Engine Running Too Hot or Cold Raw Water Engines Operate at 145° F. Closed Cooled Engines Operate at 165°-185° F
Incorrect Fuel Grade Replace
Boat Overload Check Specifications
Weight Distribution Check Specifications
Plugged or Restricted Exhaust Check Exhaust System

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 12. Trouble Shooting
Engine Starts and Stops
Possible Cause Remedy
Insufficient Fuel Supply Approximately 60 PSI. Fuel Pressure Must Be Adequate at Wide Open Throttle at Full Load
Loss of Ignition Power Check Ignition Switch, Main Engine Breaker, Engine Harness Connection

Oil Pressure - Low

Possible Cause Remedy
Low Oil Level in Crankcase Refer to Section13: Engine Identification on Page 15
Excessive Oil in Crankcase Remove Excess Oil. Refer to Section 13: Engine Identification on Page 15 for Correct Oil Level
Erroneous Oil Gauge Readings Contact Dealer to Perform a Mechanical Oil Pressure Check
Incorrect Dipstick See Dealer
Incorrect Oil Viscosity or Diluted Change to Proper Oil
Oil Pump Malfunctioning See Dealer
Excessive Bearing Clearance See Dealer
Low Oil Pressure Will Set a Trouble Code and Will Reduce Engine RPM.
Oil Pressure as Low as of 5 lbs. at Idle is Acceptable. At 2000 RPM 30 lbs. is Acceptable.

Oil Pressure - High

Possible Cause Remedy
Oil Too Thick - Wrong Viscosity Change to Proper Oil
Erroneous Oil Gauge Readings Contact Dealer to Perform a Mechanical Oil Pressure Check
Clogged or Restricted Oil Passage See Dealer
Oil Valve Relief Valve Stuck Closed See Dealer

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 12. Trouble Shooting
Excessive Oil Consumption
Possible Cause Remedy
External Leak Clean/Check/Repair
Excessive Oil in Crankcase Remove Excess Oil. Refer to Engine Identification on Page 15 for Correct Oil Level
Oil/Fuel Dilution Change Oil
Extended Excessive RPM’s Reduce RPM’s
Incorrect Oil Viscosity Change to Proper Oil
Engine Vents Blocked Unblock Vents
Defective Piston Rings See Dealer
Defective Cylinders See Dealer
Excessive Bearing Clearance See Dealer
The Amount of Oil Used is Greatly Dependent Upon Engine Speed. Oil Usage Will be Greater at Higher RPM’s.

Engine Overheating - Verify if Engine is Actually Overheating

Possible Cause Remedy
Low Coolant Level Add Coolant. Refer to Bleeding Procedure if Coolant was Low or Not Flowing into Tank
Clogged Sea Water Intake Clear Intake. Ensure That All Hoses After the Intake are Clear
Clogged Sea Water Strainer Clean Sea Strainer
Loose Hose Connections Check and Tighten Clamps
Sea Water Hose Kinked or Collapsed Verify Hose Routing and Condition
Obstruction in Cooling System Verify that Engine/Transmission Oil Cooler is not Clogged with Debris
Sea Water Pump Impeller Worn Replace
Antifreeze Not Properly Mixed Mix to a 50/50 Ratio
Heat Exchanger Core Plugged Verify that Engine Heat Exchanger Ends are not Clogged
Alternator Drive Belt Broken Replace

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 12. Trouble Shooting
Water in Engine Cylinder or Base
Possible Cause Remedy
Operator Error See Section 7: Precautions on Page 23. REMOVE Water from Engine Immediately
Exhaust Restricted or Blocked Repair or Replace. REMOVE Water from Engine Immediately
Engine and Exhaust Too Low in Boat Reroute Exhaust Hoses or Add Riser Spacers. REMOVE Water from Engine Immediately
Defective Exhaust Riser Gasket Contact Dealer. REMOVE Water from Engine Immediately
Defective Exhaust Manifold or Riser Contact Dealer. REMOVE Water from Engine Immediately
Cylinder Head Gasket Leak Contact Dealer. REMOVE Water from Engine Immediately
Cracked Block or Cylinder Head Contact Dealer. REMOVE Water from Engine Immediately
Intake Manifold Gasket Contact Dealer. REMOVE Water from Engine Immediately
Incorrect Engine Rotation Contact Dealer. REMOVE Water from Engine Immediately
Remove water by removing spark plugs and turning the engine over by hand. Once water is removed spray cylinder with Marvel Mystery Oil or 2-Cycle Engine Oil. Drain all the oil
and change the oil filter(s). Again, turn the engine over by hand to circulate the oil. Contact your dealer immediately to make the required repairs. Upon completion of repairs, run
the engine and again change the oil.

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 13. Installation Instructions
NOTE: Before shipment, each engine has been carefully tested • Front of boat is bow (50% antifreeze + 50% water) and seawater for cooling. The
and inspected. It may be necessary to delete or add oil from closed cooling system will operate at 170° - 190° F. The system
• Rear of boat is stern
the engine and transmission for various engine installations. If is monitored by the water temperature gauge on the instrument
engine is equipped with a closed cooling system, it is imperative • Right side is starboard panel and, in the case of EFI, the Engine Control Module. On EFI
to fill the system with a 50/50 mix of ethylene glycol base anti- • Left side is port engines the ECM will activate the POWER REDUCTION MODE if
freeze and clean fresh water. Failure to use a 50/50 mixture of the engine temperature reaches 210° F. The POWER REDUCTION
antifreeze and water can result in engine damage. The raw water (or Sea Water) pump is located at the front of the MODE reduces RPM to approximately 2500. The cooling system
engine on the crankshaft pulley. Engine rotation can be deter- must receive a sufficient amount of sea water under all operating
(See Section 3: Engine Identification) mined by looking at the stern end of the engine and observing the conditions to operate properly. Cooling water may be supplied
Engine Compartment flywheel rotation. Do not assume engine rotation by looking at from a stern drive unit or a through hull inlet scoop. ENPACS
the propeller rotation; it may not be the same. This information mated with stern drives that have water pumps in the drive leg
The engine compartment should be well-planned giving is critical when ordering parts for your engine. can use the water supply from the leg without using an impeller
consideration to accessibility and ventilation. Engines must have
Left Hand Engines: CCW or Normal Rotation seawater pump. If the ENPAC is equipped with closed cooling, a
air as well as fuel to operate efficiently. The battery should be
sea water pump will be part of the engine configuration and a
located as close as possible to the starter motor so that the battery Right Hand Engines: CW or Opposite Rotation
through hull inlet scoop must be used. In that case, the through
leads can be kept short. EFI engines equipped with the SMART
DI Engines are NOT Available in Right Hand Rotation. hull fitting and sea cock should be placed as close to the engine
START option have a direct connection to the battery or battery
as possible and be one size larger than the water pump inlet. The
switch. Engine wiring harness includes notation on Red/White Engine Bed water pump inlet scoop should face the bow of the boat in an area
wire.
The engine bed should be of horizontal design and heavily where there are no obstructions. Obstructions could cause water
Engine Mounting constructed to maintain engine alignment. All of the thrust used turbulence and prevent a solid stream of water from entering the
in moving the boat is transferred to the hull through the engine sea scoop. Regardless of the supply (stern drive or inlet scoop)
Engine installation is very important. If the angle is severe (over
bed. The standard engine has support mounts that are intended the coolant water inlet hose must be of a non-collapsing type. If
12 degrees) oil capacity may need to be adjusted.
to be used on engine beds arranged for 22½” - 24” bolt centers. a through hull inlet scoop is used, it is highly recommended that
Engine Rotation Use adequate bolts for each support. Make certain there is no a sea strainer of adequate size and capacity be installed between
interference on the underside of the engine between the oil pan the sea cock and engine sea water pump. If no sea strainer is
Directional references used in this section are given as if standing or other components located in that area and the hull. installed, periodically check the cooling inlet piping and hose
behind the boat, looking forward: to clear debris from engine and transmission oil coolers. Debris
Cooling System entering the cooling system is one of the main causes of over-
Closed cooled engines use a combination of freshwater coolant heating.

40 www.MarinePowerUSA.com
 13. Installation Instructions DANGER
The ABYC and other industry standards require the use of a PERMEATION DIURNAL TEST Exhaust Piping
seacock on certain types of applications to stop the entry of water STANDARDS STANDARDS TEMP
[grams per sq. meter [grams per gal. [degrees Celsius] IMPORTANT: The boat manufacturer or installing dealer (or
in the event of a leak in the cooling system. The seacock must
individual) is responsible for properly locating the engine and

WARNING
provide a minimum restriction to water flow. A 90 degree ball per day] per day]
installing the exhaust system. Improper installation may allow
valve with a lever quarter turn handle is the most commonly used Fuel Hoses 15.0 — 23 ± 2 water to enter the exhaust manifolds and engine cylinders and
type. Fuel Tank 1.5 — 28 ± 2 severely damage the engine. Damage caused by water in the
SPORTPACS AND TOWPACS use thru-hull fittings to supply Trailerable Boat 0.40 25.6 – 32.2 engine will not be covered by the Marine Power warranty,
cooling water to the sea water pump. Non-trailerable Boat 0.16 27.6 – 30.2 unless this damage is a result of defective parts or workmanship

CAUTION
by Marine Power.
Emission-Related
Installation Instructions ENPACS, SPORTPACS, JETPACS AND TOWPACS are equipped
DO NOT operate engine without water being supplied to raw water with a wet exhaust system in which exhaust is mixed with water
Failing to follow these instructions when installing a certified in the exhaust risers. This water cools the exhaust and allows the
pump as damage to the impeller and engine will result.
engine in a vessel violates federal law (40CFR 1068.105(b)) and use of heat resistant rubber hose on the riser outlets. Follow these
is subject to fines or other penalties as described in the Clean general guidelines when designing and installing the exhaust
Air Act. The installer and/or vessel manufacturer must meet the system.
evaporative emission requirements of 40 CFR part 1060 and CFR
1045.112. Use heat resistant hose that complies with specifications SAE
J2006 or UL 1129 (ABYC standard). Exhaust hoses should be 4”
Any manufacturer installing a high performance engine must on dual outlet systems. 6.2L and larger engines should use 5” on
use enhanced evaporative control systems on any boat that is single outlet systems.
manufactured for sale, sold, or offered for sale in California,
or that is introduced, delivered or imported into California for Sharp bends should be avoided.
introduction into commerce. Exhaust hoses should be connected straight on the riser outlets.
Enhanced evaporative control system has designed the system Exhaust back pressure test should be preformed to ensure that
components to meet or exceed the diurnal and permeation design exhaust components are adequately sized. Exhaust back pressure
specifications listed in the following table throughout the useful should be between 1-3 PSI. Some back pressure is necessary to
life of the engine. prevent water intrusion. Do not go below 1 PSI.
Exhaust risers must be the suggested distance above the water

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 13. Installation Instructions
line. Install riser spacers if necessary. Electrical Connection engine is running off its own battery.
A minimum of 18” of exhaust hose must be installed between the NOTE: Marine Power EFI engines are equipped with “Smart Battery Isolators
exhaust risers and the collector, Y-pipe, muffler or first angular Start” this feature is common in late model automobiles but is
fitting. This portion of the exhaust hose must have a downward Many boats are equipped with auxiliary batteries. Such bat-
new to the boating industry. This feature enables the operator
slope of 1-1/4”/ft. for conventional inboards and a downward teries are used to operate stereos, etc. Battery isolators can be
to start the engine by momentarily engaging the key switch, it is
slope of 7/8”/ft. for V-drives. Some OEM installations may used to charge an auxiliary battery. In these cases, the alternator
not necessary to hold the key switch. The ECM maintains the start-
different from these specifications but these installations have output is connected to the center post on the isolator instead of the
er engagement until the engine starts. Once the engine starts,
been carefully evaluated by Marine Power and the OEM. starter. The owner should familiarize himself with the isolator’s
the ECM prevents the starter from engaging even if the operator
operation.
After the first 18” the exhaust system must have a drop of 1/2”/ mistakenly turns the key switch. To ensure proper operation of
ft. Measure exhaust riser height as shown. Minimum exhaust riser this feature, the engine wiring harness includes an 18 gauge Engine Battery Specifications
height should be 15” on 6.0 and 6.2L engines. All others should wire coiled by the starter. This wire must be connected directly
to the battery or the battery switch. Do not connect this wire to Model Minimum Required Rating
be 13”.
the starter post as the voltage drops excessively at this location 4.3L 550 CCA
The slope in the exhaust hose and components must be rout- during starting. 5.3L 650 CCA
ed so that no low point exists in the system where water may 6.2L 750 CCA
be retained. The muffler, collector and exhaust hoses must be Batteries
adequately supported for proper routing and to prevent over Tapered post connections with wing nut connections can be used.
stressing the exhaust manifolds and risers. The tapered posts must be used for the engine battery cables
Internal flappers may be required on naturally aspirated 6.0 and while the wing nut connections should only be used for acces-
6.2L engines. sories. We highly recommend that wing nuts be replaced with
regular nuts to increase the tightness of the connections.
Applications with through transom exhausts must be equipped
with exhaust flappers to prevent the reverse flow of water into the Pay particular attention to ground connections. EFI engines are
engine. Exhaust outlets should be above the water line with the very dependent on secure ground connections. See typical ground
boat at rest to minimize engine back pressure. location.
Every exhaust connection should be secured with at least 2 hose Dual Engines
clamps. The clamps should be stainless steel and at least 1/2”
wide. Batteries: Vessels with twin engines should have a battery for
each engine. The battery switch should be positioned so each

42 www.MarinePowerUSA.com
 13. Installation Instructions
Battery Cable Length Requirements the fuel tank pick up tube should be no more than 30”. The fuel Hoses and Fittings: Use only USCG Approved fuel lines. Make
pump must also be placed as low to the bottom of the fuel tank sure that the fuel line routing is not touching any sharp edges.
Cable Length Cable Gauge as possible. Using the lowest point on the bottom of the fuel tank, Fittings should be full flow design and not restricted tight 90
Up to 3.5 ft. 4 mount the fuel pump no more than 12” above the bottom of the degree elbows.
3.5 - 6.0 ft. 2 fuel tank. USCG REGULATIONS require that the fuel pump should
6.0 - 7.5 ft. 1 be within 12” of the engine (excepting Airboats).
7.5 - 9.5 ft. 0 The Racor fuel/water separator should NEVER be placed on the
9.5 - 12 ft. 00 outlet side of the Aero Motive fuel pump. The fuel filter/water
12 - 15 ft. 000 separator should also be mounted within 12” from the bottom
15 - 19 ft. 0000 of the fuel tank.

Special Fuel Instructions for 6.2 LT4 Engines

Fuel Supply: The fuel supply pick up tube, fuel lines and
fittings shall be no smaller than 1/2” inside diameter between the
fuel tank and the Aero Motive high-pressure fuel pump. The fuel
pump must also have the supplied serviceable 100 Micron filter
installed on the inlet side of the fuel pump. Some installations
use an in-tank fuel pump. In these cases, the 100 micro filter or
water separator is not necessary. Always mount a 10 micro filter
between the pump and the injectors. When using an auxiliary
engine such as an outboard motor, never plumb or tee into the
main engine fuel system. The auxiliary engine shall have its In-Tank LT4 Pump #438639
own fuel pick up tube and fuel filter/water separator from the LT4 Fuel Pump #438627
fuel tank. Plumbing into the main engine fuel supply will cause Filter Case (10/100 Micron) #395536
damage to the engine and fuel pump system. Filter Element 10 Micron #395538
Fuel Pump Location: If the Aero Motive fuel pump is relocated Filter Element 100 Micron #395548
from its mounting location on the engine it must be placed as
close to the fuel tank as possible. The maximum distance from

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 13. Installation Instructions
Airboat Installation Notes:
All GEN V DI engines require modified belt drive housings.
Century Drive is aware of the required modifications. Engines
require engine oil coolers. LT4 engines require radiators for

DANGER
intercooler heat rejection. Intercooler radiator should be large
enough to maintain Manifold Air Temperature at WOT. Please
note there are 2 bleed points on the LT4 intercooler. Verify that
coolant is flowing through the system before before running the
engine at higher rpm’s.

WARNING
The LT4 Is a Premium 93 Octane REQUIRED engine. The engine will
operate at significantly reduced power output with octane levels
down to 90. Operating the LT4 on fuel below 90 Octane can result

CAUTION
in engine damage and or failure! Such failure will not be covered
under warranty!

44 www.MarinePowerUSA.com
 13. Installation Instructions
Adapter Harness for Analog Instrumentation
Harness M6 - 21 Pin to 10 Pin #473063

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 13. Installation Instructions
Adapter Harness for Digital Gauges
Harness M6/M7 #472908

46 www.MarinePowerUSA.com
 13. Installation Instructions
Adapter Harness for Digital Faria Panel
Harness MEFI 6/7 #472922

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 13. Installation Instructions
Heater Connections

LT4 Engine

4.3/6.2 DI

From Heater
To Heater

48 www.MarinePowerUSA.com
Prestart Checklist 7. On inboard, V-drive and stern drive applications verify that 10. Check that all engine mounts are tight
the engine will not start unless the shifter is in the neutral
1. Check engine, transmission and V-drive (if applicable) oil 11. Check that the battery is secure, and that all electrical
position.
levels. Also check for any oil leaks and repair as needed. onnections are tight.
8. On jet drive applications, check for proper operation of the
2. Check that all engine drain plugs are installed and
reverse bucket and adjust as needed.
tightened. New engines may be shipped with drain plugs
removed 9. Inspect the fuel system for leaks and repair as needed.
3. If engine is equipped with optional closed cooling system,
check for proper coolant level. Closed cooling systems must
be filled with a 50/50 mixture of ethylene glycol based
anti-freeze and clean fresh water. (See Routine Maintenance
Section for “Filling” instructions) When properly filled,
ensure that any/all fill caps, fittings and hoses are properly
secured and not leaking.
4. If engine is raw water cooled check the system for leaks and
correct as needed.
5. On engines equipped with Electronic Throttle Control (ETC)
there may be a cable routed from the throttle control
lever at the helm to a potentiometer located in the engine
compartment. Make certain that this cable operates freely and is
properly adjusted. The adjustable potentiometer stop
screws must not be used as the stop for the throttle
lever/cable assembly at the helm.
6. Check the transmission shift cable/lever adjustment on Potentiometer
Inboard, V-drive and stern-drive applications with mechan- Assembly
ical shift. If the transmission is equipped with electric shift,
check for proper operation of the shift solenoids (ahead and
astern). Refer to your transmission operation manual.

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 13. Installation Instructions
Potentiometer Operation
The throttle lever rotates assproximately 80°. Maximum clockwise
(CW) rotation is idle. Maximum counter-clockwise (CCW) rotation
is wide open throttle (WOT). The Potentiometer has contacting
wiper blades which produce 2 output voltages (PPS1 and PPS2).
Both PPS1 and PPS2 output voltages should be adjusted to .78
volts at idle and 4.1 volts at WOT. If the output voltages are above
or below these settings an “Out of Range” DTC will set and the
throttle plate will not open or close. Likewise, if the dual output
voltages differ by more than 8%, a “Correlation” DTC will set and
the throttle plate will not open or close. The set screws are used to
accurately adjust the output voltages. They are not to be used as
stops for the throttle cable. Such use will cause a Correlation DTC.
DTC’s will automatically reset with an ignition switch recycle. If the
set screws are impeding lever operation they must be backed out.
If a Correlation DTC continues to set, the Potentiometer should be
replaced as it is permanently damaged. if the Out of Range DTC
is setting as soon as the ignition is turned on, the likely cause is
mis-adjustment of idel outputs. if the Out of Range DTC occurs at
WOT, the WOT outputs are out of adjustment.

D PPS2 5V REF POS Description Wire Color

C PPS1 RETURN E PPS2 SIGNAL A PPS 1 5VOLT REF Gray
B PPS1 SIGNAL
F PPS RETURN B PPS 1 SIGNAL Blue
A PPS1 REF
C PPS 1 RETURN Black
D PPS 2 5VOLT REF Gray/White
E PPS 2 SIGNAL Blue/White
PPS1 Voltage is determined by measuring between PPS 1 Signal and PPS 1 Return (A and C). PPS 2
Voltage is measured between PPS 2 Signal and PPS 2 Return (E and F). Connector will have to be back F PPS 2 RETURN Black/White
probed with ignition on.

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 Warranty Registration Transfer
Please complete this form when engine ownership has been transferred. Transfer Registration To:

Date of Transfer (MM/DD/YY)

Engine Serial Number Engine Serial Number (If Dual Application)

Last Name First Name MI

Street Address

City State Zip Code

New Owners Phone Number

Please enclose check or money order in the amount of $300.00 per engine to be transferred. You may pay by credit card. Complete the information below.
VISA MASTERCARD
Card Number: _____________________________________________________________________ Exp. Date: ______________________________________
Name As It Appears On the Credit Card: _________________________________________________________________________________________________
Signature: _______________________________________________________________________________________________________________________
Mail completed form to: Warranty Registration Transfer, Marine Power, 17506 Marine Power Industrial Park, Ponchatoula, LA 70454

www.MarinePowerUSA.com 51
 Service Log
SERVICING DEALERS
Note: If You Are Unable to Locate an Independent Servicing Dealer.
Please Contact a Marine Power Distributor Closest to You for Further Assistance.

Date Service/Maintenance Performed Performed By Operating Hours

52 www.MarinePowerUSA.com
 Service Log
Date Service/Maintenance Performed Performed By Operating Hours

www.MarinePowerUSA.com 53
 Copyright 2019 Marine Power
All rights reserved. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying,
recording or any information storage and retrieval system, without permission in writing from MARINE POWER HOLDING, LLC.
Marine Power 17506 Marine Power Industrial Park, Ponchatoula, LA 70454 USA www.MarinePowerUSA.com