mjm yachts 40z Downeast User manual

Note: This manual is published in accordance with ISO standard 10240:1995E Small Craft - Owner’s Manual
89 Pinckney Street, Boston MA 02114
Tel [phone] Fax [phone]
July 2009
Dear 40z Owner:
Congratulations on becoming Captain and Owner of the world’s best built and most fuel efficient yacht of its size.
The enclosed copy of the 40z Owner’s Manual should further contribute to your enjoyment and proficiency afloat.
This manual was created jointly with Zurn Yacht Design, Boston BoatWorks and MJM Yachts. Our experience
with the first 102 boats (34z’s and 29z’s included) has been incorporated to make this manual as useful and relevant
as possible. Keep in mind that there maybe some variances such as location of the breakers on the panel. And, from
time-to-time we will change specifications to keep pace with changes made to improve the boat.
When addressing a problem with a specific piece of equipment, this 40z Owner’s Manual is to be regarded only as a
preliminary source of information. The equipment manufacturer’s own manual with trouble-shooting procedures,
etc. is the primary source and authority.
A National Marine Manufacturer’s Association (NMMA) publication Sportfish, Cruisers, Yachts accompanies, and
forms part of, this 40z Owner Manual. This booklet has many universal handling and operating tips worth
reviewing.
This Owner’s Manual is designed to be a living document, not only for builder updates but for your own use and
record. Each boat is provided with a copy of the current Manual organized in a STAPLES “Mini-Ring” type binder
that allows you to add pages as needed.
One of the great advantages of purchasing a series-built or semi-custom design is that owners have the benefit of
learning from one another. So, with your continued input and comments we can keep adding useful information and
helpful hints to this manual.
Part of the ISO CE Mark Certification Program is confirmation by the owner that the manual has been received.
Please sign the extra page No. 3 included in the Manual as a receipt and return it in the stamped envelope provided.
Best wishes for fair winds and sunny skies. On behalf of the builder and designer, we are most appreciative, and I
am particularly honored, that you have chosen the 40z.
Robert L. Johnstone
Chief Operating Member

Note: This manual is published in accordance with ISO standard 10240:1995E Small Craft - Owner’s Manual
Length Overall (Including Swim Platform and Bow Roller) 43.1 ft.
Length on Deck 40.0 ft.
Length Waterline 31.3 ft.
Beam 12.0 ft.
Hull Draft/Max Draft with Drives Down 2.4 ft/3.3 ft.
Displacement (1/2 load) 17,900 lbs.
Fuel Tanks (combined) 350 gals.
Fresh Water Tank 100 gals.
Hot Water Tank 13 gals.
Holding Tank 25 gals.
Height over Water (w/ radar mounted directly on hard top) Approx 10.0’ ft.
Height over Road (w/ radar on trailer) Check, as will vary by trailer. Approx. 13.4 ft.
40z

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BOAT INFORMATION
BOAT
MODEL: 40z Downeast
HULL SERIAL # (HIN): EOU40Z05E909
DESIGN PATENT: Patent No. US D475.338S (3Jun03)
DELIVERY DATE: ________
REGISTRATION#:
ENGINES
MAKE: Cummins
MODEL: QSD4.2 350 HP
SERIAL #: 88417170 stbd 88417163 port
Cummins 24 Hour Service Boat Service at 781-329-1750, 781-751-1241 (8am-5 pm)
DRIVES
MAKE: Mercruiser w/AXIUS Controls
MODEL: Bravo 3X Stern Drives
SERIAL #: stbd OW981279 Drive/1A433600 Transom
port OW981279 Drive ?/1A433599 Transom
RATIO: 1.8:1
PROPELLERS
MAKE: Mercruiser
BLADES: 2- 48-82366SL BRV3 15.5/2L24CU
2-48-823666L BRV3 14.5/4R24CU
MJM YACHTS, LLC
CONTACT: Robert L. Johnstone
PHONE: [phone] MA
MOBILE: [phone]
FAX: [phone]
Email: [email protected]
ADDRESS: 89 Pinckney St., Boston MA 02114
NAVAL ARCHITECT
NAME: Doug Zurn
FIRM: Zurn Yacht Design
PHONE: [phone]
ADDRESS: 89 Front St., Marblehead, MA 01945
LICENSED BUILDER
NAME: Boston BoatWorks, LLC
CONTACT: Scott R. S. Smith
PHONE [phone]
MOBILE [phone]
FAX [phone]
EMAIL [email protected]
ADDRESS 256 Marginal St., Boston MA 02128
DEALER
NAME:
PHONE:
ADDRESS:

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CE CERTIFICATION
CERTIFICATE NO. BBBW003 (pending)
AUTHORITY: International Marine Certification Institute
ADDRESS: Rue Abbe Cuypers 3
B-1040 Bruxelles, Belgique
PHONE: [phone]
WEBSITE: www.imci.org
CLASSIFICATION: ISO CE Mark Design Category A Ocean (EC Directive 94/25/EC) for craft
designed for offshore voyages (1) where the vessel is correctly handled
in the sense of good seamanship and operated at a speed appropriate to
the prevailing sea state and (2) with significant wave heights above 4 m
(calculations are based on 7 m) and wind speeds in excess of Beaufort
Force 8, but excluding abnormal conditions, e.g. hurricanes.
CAPACITY
PERSONS: Maximum 16 Persons
PERSONS/GEAR: Maximum Load 3518 kg
--------------------------------------------------------------------------------------------------------------------------------------------
RECEIPT BY OWNER In compliance with ISO 10240:1995(E) the owner hereby certifies receipt
of this manual and has read and agrees to the terms of the Builder’s Limited Warranty included herein.
Signature
Printed Name Date
Boat Name Hull #
Address
City, State, Zip
Tel.
Email
NOTE: PLEASE SIGN ONE OF THE TWO COPIES OF THIS PAGE AND RETURN IT IN THE
ATTACHED STAMPED ENVELOPE TO: MJM YACHTS at 89 Pinckney Street, Boston MA 02114.
Denotes an extreme intrinsic hazard exits which would result in high probability of
death or irreparable injury if proper precautions are not taken.
Denotes a hazard exists which can result in injury or death if proper precautions
are not taken.
Denotes a reminder of safety practices or directs attention to unsafe practices
which could result in personal injury or damage to the craft or components.

TABLE OF CONTENTS
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CHAPTER 1 OPERATION
1.1 GENERAL
1.2 QUICK START GUIDE
1.3 OPERATING PROCEDURES
1.4 NAVIGATION
1.5 TOWING
1.6 HAULING OUT
CHAPTER 2 SAFETY EQUIPMENT
2.1 GENERAL
2.2 FUEL SHUT-OFFS
2.3 FIRE
2.4 FIRST AID
CHAPTER 3 PROPULSION SYSTEM
INTRO – TOP 10 REASONS of ENGINE FAILURE
3.1 GENERAL
3.2 COOLING
3.3 LUBRICATION
3.4 ZINCS & CORROSION
3.5 AIR INTAKES
3.6 ENGINE DISPLAY PANEL
3.7 THROTTLE/SHIFT LEVER
3.8 STARTING
3.9 ALARMS
3.10 STOPPING
3.11 OPERATION
CHAPTER 4 STEERING SYSTEM
4.1 SYSTEM DESCRIPTION
4.2 JOYSTICK DOCKING
4.3 HELM STATION PICTURE
4.4 SWITCH PANEL FUNCTIONS
4.5 TRIM TABS
4.6 AUTOPILOT OPERATION
4.7 WINDSHIELD WIPERS
4.8 SPOTLIGHT
4.9 HELM POSITION RISER
CHAPTER 5 FUEL SYSTEM
5.0 GENERAL
5.1 FUEL SHUT-OFFS
5.2 FILLING
5.3 RACOR FUEL FILTERS
5.4 FUEL CONSUMPTION & LOG
CHAPTER 6 ELECTRICAL SYSTEM
6.0 GENERAL
6.1 DC SYSTEM
6.2 AC SYSTEM
6.3 GENERATOR
6.4 INVERTER
6.5 REVERSE POLARITY
6.6 ELECTROLYSIS & ZINCS
6.7 BONDING
6.8 ELECTRICAL SAFETY
6.9 FUSE LOCATIONS/SPECS
CHAPTER 7 FRESHWATER SYSTEM
7.0 GENERAL
7.1 FILLING
7.2 FRESH WATER PUMP
7.3 HOT WATER
7.4 WATER PURIFIER
CHAPTER 8 RAW WATER SYSTEM
8.1 GENERAL
8.2 ENGINE RAW WATER
CHAPTER 9 GRAY WATER SYSTEM
9.1 GENERAL
9.2 GRAY WATER SUMPS
9.3 BILGE PUMPS
9.4 COMMON DRAINS
CHAPTER 10 EXTERIOR EQUIPMENT
10.1 GENERAL
10.2 ANCHOR WINDLASS & WASHER
10.3 PILOTHOUSE CURTAINS
10.4 PRIVACY & SUNSCREEN CURTAINS
10.5 TRANSOM DOOR & SEAT
10.6 STIDD SEAT POSITIONING
10.7 WINDSHIELD OPERATION
CHAPTER 11 INTERIOR EQUIPMENT
11.1 MARINE HEAD SYSTEM
11.2 REFRIGERATION
11.3 COOKTOP
11.4 MICROWAVE/OVEN
11.5 AIR-CONDITIONING (Optional)
11.6 HEATING SYSTEM (Optional)
11.7 STEREO & CD CHANGER
11.8 SIRIUS SATELLITE SYSTEM
11.9 TELEVISION
11.10 SATELLITE TV RECEIVER
CHAPTER 12 ROUTINE MAINTENANCE
12.1 SCHEDULE
12.2 FLUIDS
CHAPTER 13 SEASONAL MAINTENANCE
CHAPTER 14 FIGURES
14.1 EMERGENCY DIAGRAM
14.2 DC SCHEMATIC (12 VOLT)
14.3 AC SCHEMATIC (120 VOLT)
14.4 SYSTEMS DIAGRAM
14.5 SYSTEMS KEY
14.6 TRAVEL LIFT SLING DIAGRAMS
14.7 TRUCKING CHECKLIST
CHAPTER 15 LIMITED WARRANTY
CHAPTER 16 QUICK START

CHAPTER 1 OPERATION
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1.1 GENERAL
This manual has been compiled to help you operate your yacht with safety and pleasure. It
contains details of the yacht; the equipment supplied or fitted, its systems, and information on its
operation and maintenance. Please read it carefully, and familiarize yourself with the yacht
before using it.
If this is your first yacht, or you are changing to a type of yacht you are not familiar with, for your
own comfort and safety, please insure that you obtain handling and operating experience before
assuming command of the yacht. Your dealer or yacht club will be pleased to advise you of local
schools, or competent instructors.
PLEASE KEEP THIS MANUAL IN A SECURE PLACE ON THE BOAT, AND HAND IT OVER TO
THE NEW OWNER IF YOU EVER SELL THE CRAFT.
This Owner’s Manual is not intended to be a course in boating safety, boat handling, navigation
or general boating skills. It is the responsibility of the user to independently gain these skills.
Instead, this manual will serve as a reference for matters specific to the 40z. Standard options
are included in the manual with which your particular yacht may or may not be fitted. Custom
options may be addressed in an addendum.
1.2 QUICK START GUIDE (See CHAPTER 16)
A separate “Quick Start Guide” is included that briefly reviews the key items to check before
departure. Please review the topics in this manual before relying on the checklist – it is simply an
“at-a-glance” sheet to insure that you don’t overlook anything important.
1.3 OPERATING PROCEDURES – ENGINE INSPECTION
To access the propulsion system, the cockpit engine hatch must be raised. The procedure is as
follows:
Make sure personnel and equipment are clear of any moving parts before
operating.
- Turn ON house battery switch (located under the electrical panel)
- Turn ON DC main disconnect breaker & engine hatch breaker at the DC panel
- Activate the lift with the small black toggle switch located in the starboard cockpit seat locker.
1.4 NAVIGATION
The builder installed navigation system includes autopilot w/compass, depth sounder, chart-
plotter, and radar. Modern marine electronics are a subject unto themselves and you should refer
to the manuals that came with the equipment you purchased. However, here are a few points to
consider:
If you are unfamiliar with navigation, educate yourself before using the boat. Electronic
equipment is NOT a substitute for dead-reckoning navigation skills.
It is not recommended to rely solely on electronic charts- bring paper chart back-ups.
It is prudent to check (or have checked) your compass alignment once the boat is in your
primary area of operation. See the Ritchie instructions for compensation.
Check that all equipment is functioning, even if you intend not to use it.
Radar and its overlay projection on the plotter should be properly aligned (Double-check
when underway) See manual to adjust, tune and operate.

CHAPTER 1 OPERATION
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Compass Heading & Calibration
There are 3 heading references for navigation on the 40z: (1) The compass on the dash, (2)
Autopilot digital compass, and (3) GPS COG (Course Over Ground). All of these headings should
be within a degree or so of each other when underway. If not, it is recommended that differences
be recorded on a deviation card after following the calibration method outlined below or
employing the services of a compass adjuster. Use COG as the primary reference at a time
when you are not influenced by wind/wave/tidal set. The digital compass sensor is located on a
stringer outboard to port under the cabin sole. It is accessible by opening the cabin sole hatch
and looking aft and to port. Avoid storing steel or iron items such as tools
next to it.
Ritchie Ship’s Compass Calibration Method
1) With the compass in its intended position, but not finally secured, select a course on your chart
using two identifiable marks, buoys or landmarks that are within ten degrees (10°) of the
north/south line. Try to select this course so that you can maneuver your boat "down range" of
the marks selected.
2) From a position down range of the North/South marks, and keeping the marks lined up, run
the boat visually along the northerly course selected. Turn the port/starboard compensator on the
right side of the compass until the compass reads correctly.
3) Reversing direction, run the boat southerly, again keeping the marks lined up. If the compass
is not correct at this time, there is an alignment error. To correct, rotate the compass itself to
remove one half of this error. Repeat Steps 1 and 2 and then recheck this Step 3.
4) Simply repeat the procedures of Steps 1, 2 and 3, except this time, using an east/west course
and the fore/aft compensator on the aft face of the compass housing, although at this time any
alignment error should have been eliminated.
5) Upon completing the procedure, secure the compass in its final position.
Boat Speed Rather than a paddle wheel or sonic device, the Raymarine C120 plotter is used to
generate SOG (Speed Over Ground) that is displayed by the chart-plotter and may also be
shown in larger digits on the Autopilot display. Eventually, you will learn to approximate boat
speed through the water by relating it to RPM on the tachometer.
1.5 TOWING
Refer to the included NMMA publication “Sportfish, Cruisers, Yachts – Owner’s Manual” for
towing instructions.
1.6 HAULING OUT
A facility that is unfamiliar with the 40z may require information before hauling the boat with a
Travelift or crane & straps. Refer to the illustration included at the back of this manual. The keel
(centerline of the boat) and chines (edges) should be used to position weight-bearing supports.
You will note that the fore and aft lift points are located approximately at either end of the
pilothouse... e.g. abeam of the windshield and the aft end of the hard top.
Point loading flat areas other than centerline and chine or setting the weight of
the hull on supports of insufficient area may result in damage to the hull.

CHAPTER 2 SAFETY EQUIPMENT
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2.1 GENERAL
Spend time reviewing where your safety equipment is and how it functions BEFORE you need it.
Remember, the best way to protect yourself and others from accidents is to eliminate potential
causes of accidents before they occur. Good seamanship and common sense go a long way in
this endeavor. [See Figure 14.1]
Here is a safety checklist derived in part from the USCG Vessel Check List. State Regulations
may vary:
PFD’s
A wearable USCG approved personal flotation device (life-jacket) must be provided for each
person aboard. On the 40z, these can be types I, II, III or V. Also, one type IV throwable PFD
must be immediately available for use.
Children under 13 years of age are required to wear a USCG life jacket that fits when underway
unless they are in an enclosed cabin or belowdecks.
Visual Distress Signals (VDS)
You must carry VDS’s aboard. If operating between sunset and sunrise, they must be suitable for
night use and be within the age dates marked on the side of the flares. A minimum of 3 day/night
use combination pyrotechnic flares are required. For a list of USCG approved devices, see the
USCG recreational checklist.
Fire Extinguisher
In addition to the automatic fire suppression system fitted in the engine space, you are required to
carry at least one type B-1 extinguisher aboard, which is located outboard of the starboard helm
seat. This should be checked regularly.
EPIRB
Especially if operating offshore, an EPIRB (electronic position indicating radio beacon) is
recommended.
Ships Papers & Registration
You should carry the vessel’s registration papers and number plate.
Pollution Regulation Plaques
5”x8” Oil Discharge Plaque and a 4”x9” Waste Discharge Placard should be fixed were visible.
Charts & Light Lists
Charts, light lists and a USCG required copy of the Inland “Rules of the Road” Navigation Rules
Horn or Whistle
Recommended to signal intentions or signal position. For instance, when in a narrow channel or
the Intracoastal Waterway: To signal which side of another boat you will pass on, blow 1 blast if
you are passing to their starboard side and 2 blasts if passing on their port side. The Kahlenburg
horn has a repetitive automatic fog signal that can be activated for either underway or at anchor.
Life Raft
If you plan to be coastal cruising out of sight of land, it is prudent to carry a Coastal Life Raft
which come in compact sizes that can be stored in one of the aft cockpit lockers.
Heaving Line
These floating lines are available and handy to have ready in case of emergency or to simply trail
behind the boat when swimming, .with the end attached to one of the stern cleats.

CHAPTER 2 SAFETY EQUIPMENT
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First Aid Kit
Not a place to scrimp. It is advisable to carry a good, comprehensive, and well-organized (by
injury) marine first-aid kit with manual. We recommend that it be stored in the head and that
everyone onboard be informed of its location. (Remember, you may be the one in need of it!)
Companionway Hatch Board or Closure
A teak board is provided with the label, “ DO NOT REMOVE WHILE UNDERWAY” to comply with
ISO requirements for cockpit draining and construction to prevent large waves from crashing
down into the cockpit, running forward into the pilothouse and entering the interior of the boat. It
would be far easier and more effective in rough weather – providing more effective full closure of
the companionway entrance – to simply close and latch the companionway slider, which has the
capability to open from either on deck or from inside should someone be below.
2.2 FUEL SHUT-OFF VALVES
The fuel shut-off valves are located on top of the fuel tanks and are accessible through pilothouse
settee lockers. Make sure you know how to shut off the fuel valve. (When the handle is
perpendicular to the hose, the valve is closed.) In case of a fuel fire, STOP any machinery and
close the valve to cut the supply of fuel to the fire/engine. If you should ever see fuel in the bilges,
turn off the valve, clean the bilges, and find the source of the leak immediately. Also note that
there are fuel shut off valves, normally left open, on the lower inboard aft corner of the fuel tanks,
which connect the two tanks together at the bottom for self-leveling. There is only one fuel level
sensor and that is on the starboard tank.
2.3 FIRE
Fire aboard a boat is a serious matter, and fire safety begins with fire prevention. You can reduce
the risk of fire by following common sense guidelines:
Do not allow debris or oily rags to collect in bilges or machinery spaces.
Understand your electrical system, allow only qualified marine electricians to work on it, and shut
down as many circuits as practical when leaving the boat. Do not leave appliances running while
unattended.
Have your fire suppression equipment inspected regularly and learn how to use it.
An automatic fire suppression system is installed on every boat in the engine space. It is heat
activated. Read the information that comes with the equipment. The system can also be manually
activated at the helm station. [See Helm Console Section]Because a diesel engine would
evacuate the suppression agent from the affected space, the system will shut down the engine
(and generator) when it discharges. If manually activating the system, the engine should be shut
down first. After the situation has stabilized, the shut-down feature can be over-ridden to restart
the engine. A loud warning alarm will sound when the system has been activated.
The hand-held fire extinguisher mounted outboard of the starboard helm seat is rated to fight type
A, B & C fires.
To extinguish a fire, the most effective method is to cut the source of fuel to the fire. In the case of
a diesel fuel fire, the fuel tank valves should be closed. In the case of an electrical fire, the main
battery switches or main disconnect breakers should be turned off. Fire needs oxygen to burn, so
if a fire should occur in an enclosed area, the best course of action may be to exit the area and
seal it from the outside by closing all means of air intake

CHAPTER 3 PROPULSION SYSTEM
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INTRO - THE TOP 10 CAUSES OF ENGINE FAILURE
It doesn’t happen often and if you’re familiar with the most common causes of engine failure you can cut
down on the chances of a breakdown. As an introductory to this chapter, we want to familiarize you with
this list of causes, compiled by Motorboating Magazine (February 2006). Here are the Top Ten to be
aware of:
1. NO FUEL: This is probably less of a problem on a fuel-efficient MJM than on other boats, but lack of
owner attention to fuel consumption is the primary culprit for engine failure. A boat’s fuel tank can be
nearly dry as a bone – even when the gauge claims there’s a 1/4 of a tank left. This makes sense when
you realize that at cruising speed, the gauge shows the tanks reading higher than when the boat is at
rest. A good rule of thumb is to never pass a fuel dock (no matter what the price) if your gauge is showing
less than 1/3 full.
1b. AIR IN FUEL LINE: If air gets drawn into the fuel lines because of either a small leak in a fuel line
connection or the Racor Filter lid gasket/filter basket tabs have interfered with the lid being secured fully,
you may find the engine will turn over, but won’t start. Check the Racor to insure the fuel level is within
an inch of the top. Check the engine owner manual for the location of a manual primer pump.
1c. COMPUTER SETTING: On the Yanmar electronic engines, we’ve encountered several instances
where after shutting down the engine for several hours (on a picnic); it was only possible to start the
engine after many tries or not at all. The problem was that the setting that determines the amount of fuel
to be injected into the engine upon starting was not set high enough.
2. DIRTY FUEL: Engine problems are caused by dirt and water in the fuel. Debris, stirred up from the
bottom of the tank by wave action, is drawn into the fuel line and clogs the fuel filter element. Starved for
fuel, the engine begins to run poorly, and then not at all. Water in the fuel can drive you mad. Moisture
condenses out of the highly humid air on the inside walls of a fuel tank, then runs down into the fuel.
Water can also be introduced at the fuel dock from a contaminated fuel supply. Fuel floats on top of
water and the fuel pick ups are near the bottom of the tank. A fuel/water separator protects against this
by handily extracting the water. Check the bowl daily and drain off the accumulated water. For severe
contamination, use a fuel drying additive.
3. FUEL BUGS: Diesel engines suffer from microbial bugs growing in the fuel. If left unchecked, these
critters clog filters. If you leave the same diesel fuel in the tank for any length of time, a fuel conditioner
similar to that supplied with your boat by the builder will kill the bugs and break up any hydrocarbon
residue into particles that will burn completely in the combustion process.
4. TIRED/DAMAGED WATER PUMP IMPELLER: As boats age or if
an engine isn’t operated for a long period of time, a worn-out circulating
water pump is another engine killer. Impeller blades are commonly
made of a rubberized material that stiffens or distorts over time and can
break off entirely, reducing coolant flow and clogging the heat
exchanger. Periodic engine maintenance procedures can prevent this
problem. A spare is provided in the Yanmar Spares Kit. Shown at right
is an impeller that would have soon failed. It was discovered, then
replaced during the 50-hour inspection on a 29z that had not been run
for 11 months. Another cause for impeller disintegration is running the
engine with the raw water intake shut off. By the time that the overheating is discovered and you shut
down the engine, the impeller may already have been destroyed or damaged. This happened on a 34z
when the operator forgot to be sure that the raw water intake valve was in the proper position.
5. HARD HOSE: Another issue to be concerned about with older boats. As water intake hoses age,
they lose their resiliency and collapse under suction, causing a restriction in the flow of engine coolant.
This results in over-heating.

CHAPTER 3 PROPULSION SYSTEM
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Prevention is easy: Visually inspect cooling hoses and squeeze them to be sure they retain shape and
set.
6. CLOGGED INTAKE: Floating debris in the water is another culprit. Things like discarded plastic
baggies, weeds, etc. can plug up the raw-water intake. You can avoid this problem by visually inspecting
the strainer basket. When removing debris, be sure to properly replace the seal, otherwise the pump will
lose suction. Smearing the seal with Vaseline or other marine-grade grease helps.
7. HARD KNOCKS: Collision with an underwater obstacle that damages the propulsion system. Often
you can still operate the boat at low RPM to return to port, being careful to avoid excessive vibration that
might otherwise compound the damage by damaging the transmission. The problem may be corrected in
a day or so without hauling by an experienced diver who has access to a prop shop where the blades can
be repaired and the prop re-balanced, then re-installed.
8. BAD BATTERY: Marine starting batteries die from old age and neglect. Keep the terminals and
posts clean from that green corrosion that builds up, restricting the flow of current – preventing them from
fully charging. Periodically have your batteries tested to determine their condition and expected longevity.
The 40z is equipped with a “parallel” switch which can be turned on to employ the 400 ampere-hour
house bank in starting the engine.
9. STALE GASOLINE: Not applicable
10. SAGGING BELT: As V-belts wear, they stretch and begin to slip. Consequently, alternators and
water pumps don’t spin to their full speed. Batteries may not fully charge and coolant circulates
sluggishly. The solution is to check belt tension regularly and tighten belts when necessary. Drive belts
can also snap. The only way to avoid this malady is to replace them once they begin to show wear.
Spare belts are provided in the Yanmar spares kit

CHAPTER 3 PROPULSION SYSTEM
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3.0 PROPULSION SYSTEM
3.1 GENERAL Your 40z is propelled by twin QSD4.2 320 HP Cummins diesel engines
with Mercruiser Bravo 3x Outdrives. There are 3 Operating Manuals
CUMMINS ENGINE OPERATING AND MAINTENACE MANUAL (EOM)
CUMMINS OWNER’S MANUAL FOR SMARTCRAFT (SOM) Shows Control Levers on Cover
MERCURY OWNER’S MANUAL FOR SMARTCRAFT (MOM) Plain Black
Rather than try to duplicate the excellent instructions in each, this MJM Owner’s Manual will refer
to the appropriate pages in the following manner: See “EOM 22-23” meaning Engine Operating
Manual, pages 22-23.
Engines are accessed by raising the cockpit hatch using the electric lift black toggle switch on the
outboard wall inside the starboard cockpit seat locker.
NEW ENGINE BREAK-IN (See EOM 38-39) While
running the engine for the first time and after shut-
down, check for proper engine oil pressure, diesel fuel
leaks, engine oil leaks, coolant leaks, proper operation
of the indicators and gauges, proper exhaust color,
engine vibrations and sounds, If temperature is high
(a) Is the raw water intake seacock properly open (b)
Are the raw water strainers clogged?
RAW WATER
INTAKE STRAINERS
See EOM 55-127 for
detailed description of
components.
COOLANT CAPS
OIL DIPSTICKS
(under panel)
DRIVE LUBE RESERVOIRS
(under engine top covers)

CHAPTER 3 PROPULSION SYSTEM
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The engine may seize if it is operated when seawater intake is restricted or if
load is applied without allowing the water temperature (engine) to warm up.
During the first 10 hours of operation, full load should only be applied for short periods. Never run
the engine for a long period at a constant RPM during this period. Higher oil consumption is
typical at this time, so carefully observe oil pressure and engine temperature, exhaust color and
check engine oil and coolant levels frequently... i.e. daily.
3.2 COOLING
Your engine passes seawater (raw
water) through two 3-WAY thru-
hulls located forward of the
engines, then thru raw water filters
(indicated above) then through
pumped through the impeller to a
heat exchanger where it cools the
engine’s coolant. This coolant is
then circulated through the engine
and returns to the heat exchanger.
For the engine to keep cool, it must
have an adequate supply of raw water and coolant.
Periodically check to be sure it’s clean and check the
coolant level by opening the caps on top of the engine.
Coolant should be close to the top. See EOM 55-127.
For details on what type of coolant to use, consult the
engine operator’s manual or the maintenance schedule
included in this manual. As the water and exhaust exit
out the back of the drives, it is not as easy to check
raw water flow. It is recommended to pay close
attention to water temperature (176°-194° F is normal
at cruising speed) at the outset.
Do not attempt to remove the coolant
cap of a hot engine.
The 3-WAY RAW WATER INTAKE THRU-HULL VALVES are tricky and counter-intuitive.
“Closed” is up, not “ON” as on most thru-hulls. Confusion here has led to a couple of burned out
impellers on 34z’s. “OPEN” for engine operation is when the handles are pushed down to PORT.
“EMERGENCY PUMP” or “FRESHWATER FLUSH” is when the handles are pushed down to
STARBOARD. To operate as an emergency pump, connect hose(s) into the top hose
connection. In fact, short lengths of hose(s) with a shut-off could be attached at all times.
3.3 LUBRICATION
Both the engine and drives use oil for lubrication. The transmission will tend to use less oil than
the engine, but both should be checked frequently. For the proper type of oils to use (which may
depend on the service area and conditions), see EOM 42-46.
For inspection procedures and maintenance schedule consult EOM 50-52 and 55-127.
The engine oil may be checked on the engines using dipsticks, at least ½ hour after running of
the engines to allow the oil to drain down from the upper part of the engine.
The drive lube reservoir is located at the upper aft port corner under the plastic engine cover.
Emergency
Pump or
FLUSH
to Starboard
OPEN
to Port
CLOSED
IF UP

CHAPTER 3 PROPULSION SYSTEM
- 14 - 34z
:Cancel, Close, Off
;Enter
Propulsion Screens
Vessel Screens
Depth-Log-Nav
MENU – Toggles betw
setup menu and current
screen.
Adjust Brightness or
View active fault details
Navi
g
ate
3.4 CORROSION PROTECTION
See EOM 55-127 In addition to transom zincs, there are engine and drive zincs and care must be
taken of the drive housing and coating of the propulsion unit. Be sure to inspect and recoat if
there are any scratches or whenever the boat is hauled. The timing for replacing zincs varies
depending on the characteristics of the seawater, the amount of electrical current in marinas, or
could indicate (if excessive wear is noted) an electrical short on the boat, etc. Inspect the engine
zinc periodically at the time of oil changes and remove the corroded area on the surface,
replacing them when deteriorated to less than 50% of original size. Otherwise corrosion-cooling
system will occur and water leakage or parts breakage will result. Be sure to close the raw water
before removing a plug to replace an engine’s zinc.
3.5 ENGINE AIR INTAKES
Diesel engines use a large quantity of air for
combustion. The engine of the 40z gets this air thru grills
under the cockpit coaming, both port and starboard.
3.6 ENGINE CONTROL/DISPLAY PANEL
The VesselView Display Screen allows the operator to perform settings and choose information
displayed The entire Mercury SmartCraft Owner’s Manual (MOM) is devoted to the operation of
this display panel. Ignore the Genset Section which is only for ONAN generators made by
Cummins. There is no interface with the optional Northern Lights Generator(s) on the 40z.
3.7 THROTTLE/SHIFT CONTROL (See MOM 22)
The Standard 40z is equipped with the dual-engine, 2-lever DTS Trackpad Yacht Control
incorporating SmartCraft electronic remote control (ERC) which has a DTS trackpad integrated
onto the base of the control. The DTS trackpad is used to enable or disable features of the DTS
system, including auto-synchronization, throttle only, etc. The 40z is NOT equipped with the
TROLL feature.

CHAPTER 3 PROPULSION SYSTEM
- 15 - 34z
There are 5 positions (front to back).
FORWARD
IDLE FORWARD
NEUTRAL
IDLE REVERSE
REVERSE
SUDDEN MOVEMENT
HAZARD This control lever governs both
throttle and shifting functions. The boat may
start to move abruptly when the marine gear is
engaged: Ensure the boat is clear of all
obstacles forward and aft. Cautiously shift to the
IDLE FORWARD position then quickly back to
NEUTRAL position. Observe whether the boat
moves as you expect.
Adjustment of Control Handle Pressure &
Detente See MOM 24
NEUTRAL These neutral lights will illuminate
steadily when the engine is in the neutral gear.
Lights will flash when the engine is in the throttle
only mode.
TROLL -/+ Not applicable as trolling or reduced
idle speed functions are not available on the
QSD engines of the 40z.
SYNCHRONIZATION – Press to automatically
synchronize both engines to match RPM of the
starboard engine... if over 900 RPM and
handles within 10% of each other. IF LED is
YELLOW, conditions are not right for synch to
engage. When RED, synch is engaged. To
DISENGAGE, press “Synch”.
TRANSFER – Not applicable as it transfers
control to a different helm station.
1 LEVER OPERATION – An interesting feature that allows both engine throttle/shift functions to
be controlled with the single PORT control handle. To DISENGAGE, shift into neutral and
PRESS the “1 Lever” button.
THROTTLE ONLY – When in Neutral, PRESS and advance handle to forward detent. Horn will
sound and neutral light will flash. Horn sounds twice when throttle only is engaged. Then
advance engine RPM. To DISENGAGE, move control handle to NEUTRAL then PRESS “Throttle
Only” button. It’s the only way to turn it OFF. Allow the engine RPMs to stabilize at idle before
engaging gears.
There is also a “neutral safety feature” outlined in MOM 19.

CHAPTER 3 PROPULSION SYSTEM
- 16 - 34z
DOCKING MODE – Probably not used much with AXIUS, because the joystick will be used for
docking. This feature reduces throttle effect on RPM to 50% of its normal capacity. To
DISENGAGE, shift engines into neutral and press the “dock” button.
3.8 STARTING (See EOM 29-32)
Before starting the engine, make sure (1)
the raw water intake seacock handles are
OPEN, pushed down and to port. (2) the
raw water strainer is clean (3) the engine
has sufficient oil and coolant (4)
transmission fluid is at the proper level (5)
there are no restrictions to the air intake
grills (6) the fuel valve over both tanks are
OPEN (8) the HOUSE and BOTH
ENGINE battery banks (under the
electrical panel) are turned ON (9) the
throttle is in the neutral position showing
the yellow Neutral Lights (9) no one is in
the water near the boat and (10) all
machinery space hatches are closed.
TURN ON ENGINE IGNITION PANEL Turn the spring-loaded Ignition Keys clockwise to “ON”
(ACC stands for Accessories). After the SmartCraft display is activated and the Neutral Lights are
on, hold the switches to START.
START ENGINES by holding one then the second Ignition Key to the right with pressure to
“START” on the outer key rim, for several seconds until the engine starts. Then release the key,
so it springs back to “ON”. The engine will not start unless the shift levers are in NEUTRAL. If
repeated start attempts are needed, the key must be turned back to position OFF first.
Never engage the starter motor (turning key hard to the right) while the engine
is running. This may damage the pinion and/or ring gear.
IF BATTERY VOLTAGE is low and you have difficulty turning over the engine, a momentary
Parallel Switch is located to the left of two Engine Start Battery Switches underneath the electrical
panel belowdecks. By turning this switch on, you add the capacity of the house bank to the start
battery. Once started, turn OF the Parallel Switch. It is for emergency use only.
3.9 ALARM DISPLAY
When the ignition key is first turned ON to position, you may hear an audible alarm signal A long
continuous horn indicates that the self-test function has failed and critical fault has been found.
Turn the switch to STOP immediately, if not in a hazardous situation, investigate and correct. See
EOM 29-32
MULTIPLE FAULTS DISPLAYED on Vessel View. It may be only ONE. There are five
computers that control all the interfaces between the engines and controls and the engines with
each other. If you see as many as 14 faults showing on the Vessel View, don’t panic. The
computers probably need rebooting. Follow this procedure.
1. Shut everything down.
2. Turn the engine keys to ON
3. When the alarm Beeps, Hit EMERGENCY STOP
4. Return EMERGENCY STOP to normal positon.
Emergency
STOP

CHAPTER 3 PROPULSION SYSTEM
- 17 - 34z
3.10 STOPPING
1. Place the remote control lever in neutral.
2. Operate the engine at idle speed for several minutes to allow the turbocharger and
engine to cool.
3. Turn the key switch to the "OFF" position.
EMERGENCY STOP SWITCH See pic in 3.8. This is used to stop both engines simultaneously
in emergencies such as man overboard or tangled propeller. There is another emergency stop
button on Vessel Interface Panels (VIP) located in the cockpit floor locker forward of the engines.
Starting after Emergency Stop with engine in Gear (See SOM 6)
Avoid stopping the engine if the sterndrive is in gear. If the engine does stop with the sterndrive
in gear such as when pushing the Emergency Stop switch:
(1) Push and pull repeatedly on the remote control handle until the handle returns to the
neutral detent position. This may take several tries if the power package was operating
above idle RPM when the engine stopped.
(2) After the handle returns to the neutral detent position, turn the key switches to OFF for at
least 30 seconds.
(3) Resume normal starting procedures.
Make sure to turn OFF Engine Battery Switches under the electrical panel when leaving the boat.
3.11 OPERATION
Engine trouble can arise if the engine is operated for a long time under
overloaded conditions at max RPM. Recommended “Max Cruising Speed” is at least 10% below
full throttle. While running, pay attention to the engine data on the LCD display. A significant
change in temperature, oil pressure, or voltage should be investigated immediately, before the
engine is damaged.
OIL PRESSURE – Normally between 30 psi when idling to 93 psi
COOLANT TEMPERATURE – Normally between 176 and 185 degrees F.
OIL TEMPERATURE – Normally 192 degrees F.
CHARGING – Normally about 14 Volts when underway.
Depending on hull structure and engine installation, engine and hull resonance may be greater at
some speeds than others. This is normal and you will learn to pick the sweet spots. If you hear
any abnormal sounds, stop the engine and inspect.
If any warning lights or buzzers/horns activate, stop the engine immediately.
Determine the cause and repair the problem before continuing to operate.

CHAPTER 4 STEERING SYSTEM
- 18 - 34z
4.1 STEERING SYSTEM
The 40z has an integrated, electronically controlled hydraulic power steering system which turns
the two Mercruiser stern drives. When running, the 40z is steered as with outboards. Thrust of the
propellers is directed more immediately and precisely from side to side through a 26° arc to steer
the boat.... rather than bouncing the prop wash from a conventional straight shaft propulsion unit
off a rudder.
Control of the sterndrives is transferred from the throttle/shift levers to the AXIUS computer
controlled joystick when the throttle/shift levers are in NEUTRAL and both engines are running.
Emergency Procedure If a fault occurs which prevents one or both of the propulsion units from
being operated with the steering wheel or the transmission does not respond See SOM 63.
4.2 JOYSTICK DOCKING CONTROL
This AXIUS control is used only for docking and
maneuvering at slow speed. Learn to handle the joystick in a
safe and correct manner before you start using the function
in tight quarters.
When the joystick is active, the normal
engine controls are in Neutral and inactive. A computer
operates the drives and shifting. Rotation of the steering
wheel is frozen and it should not be turned, as damage may
occur.
To Activate: Both engines must be running and the engine
control handles must be IN NEUTRAL. Lower both drives to
the full DOWN position and preferably raise trim tabs as well.
To Deactivate: Move the engine controls OUT OF
NEUTRAL (forward or reverse).
Maneuvering with Joystick Lean the joystick post in the
direction you’d like to go. Release and the thrust stops. The
boat may keep moving, so you may have to lightly tap it in the opposite direction to stop it. The
top of the joystick is twisted to orient the bow and stern, or to spin the boat completely around on
its own axis. Pretty simple Takes some practice until it becomes completely intuitive. See SOM
26 for a more detailed description of how it works.

CHAPTER 4 STEERING SYSTEM
- 19 - 34z
Smartcraft
VesselView
AXIUS Joystick
Switch Panel
(See Below)
Bilge Pumps (3)
DTS Yacht Control
Genset Panel
Spotlight Remote
GPS
Plotter/Radar
ST 60 De
p
th
FireBoy System
Bilge Water Alarm 4”
A
utoPilot Trim Tabs
Windlass U
p
/Down
12V Cellphone Outlet
Ignition Switches
Emer
g
enc
y
E-STOP
4.3 HELM STATION
The helm station console is where most of the operational controls of the boat are located.
Become familiar with these before you need to use them. In addition, make sure that when you
are using the boat, even if you are not using a specific piece of equipment, which the circuit
breakers are on for any equipment you might need.

CHAPTER 4 STEERING SYSTEM
- 20 - 34z
NAV LTS
FWD
Underway
AFT
At Anchor
WIPERS
Washers
AUTO HORN
FWD Underway
1 Blast
AFT at Anchor
2 Blasts
Press to
Sound
HORN
Press when
Raising Rode,
Chain & Anchor
to Wash with
Fresh Water
PORT - STBD
OUTDRIVE
TRIM
BUTTONS
4.4 CONSOLE SWITCH PANEL
With the exception of the Anchor Washdown which is activated along with the “Windlass” breaker
(and must have the “Water Pressure” switch ON as does the washer function of the “Wiper”
switch) functions of this panel on the console are activated by turning on their respective breaker
switches on the DC Electrical Panel in the main saloon. Functions of the panel rocker switches
are described below the corresponding switch:
4.5 TRIM TAB SYSTEM
The trim tab breaker on the DC panel must be ON for
the unit to work. The vertical series of lights, on either
side of the Lenco panel are wired intuitively, so by
pushing down the starboard tab, the lights appear as
the bow leans down to starboard. (What’s physically
happening under the boat is: the port tab is going down
to lift the port aft corner of the boat to drop the
starboard bow).
Normally tabs are adjusted simultaneously with 2
fingers.
Trim tabs aren’t necessary at low or high speeds.
At speeds over 8 knots, trim tabs allow you to trim the
boat from side to side to compensate for crew location, gear placement or to counteract wind
pressure. The boat leans into the breeze. They are useful in lowering the bow for better visibility
or for powering into waves without pounding. Don’t hesitate to apply maximum tabs in the 15-22
knot range. At higher speeds in smooth water,when the boat naturally runs flatter or when running
downsea into the back of waves, it’s advisable to raise the trim tabs for dry running and control,
allowing the bow to lift.