Yanmar ZT370 User manual

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English
STERN-DRIVE
OPERATION MANUAL
ZT370

MODEL
OPERATION MANUAL CODE
All Rights Reserved, Copyright
ZT370
0AZTD-EN0022
Disclaimers:
All information, illustrations and specifications in this manual are based on the latest
information available at the time of publishing. The illustrations used in this manual
are intended as representative reference views only. Moreover, because of our
continuous product improvement policy, we may modify information, illustrations
and/or specifications to explain and/or exemplify a product, service or maintenance
improvement. We reserve the right to make any change at any time without notice.
Yanmar and are registered trademarks of YANMAR CO., LTD. in
Japan, the United States and/or other countries.
All Rights Reserved:
No part of this publication may be reproduced or used in any form by any means -
graphic, electronic, or mechanical, including photocopying, recording, taping, or
information storage and retrieval systems - without the written permission of
YANMAR CO., LTD.

ZT370 Operation Manual i
ZT370 Operation ManualTABLE OF
CONTENTS
Page
Introduction..................................................................... 1
Record of Ownership ................................................. 2
Safety............................................................................... 3
Safety Precautions ..................................................... 4
General Information ............................................. 4
Before You Operate............................................. 4
During Operation and Maintenance..................... 4
Product Overview ........................................................... 9
Overview .................................................................... 9
Owner/Operator Responsibilities ......................... 9
New Stern-Drive Break-In:................................... 9
Dealer/Distributor Responsibilities..................... 10
Component Identification ......................................... 11
Location of Serial Numbers ............................... 12
Corrosion Protection ................................................ 13
Galvanic Corrosion ............................................ 13
Corrosion Control .............................................. 13
Shore Power ...................................................... 13
Underwater Drive Coating ................................. 14
Additional Protection.......................................... 14
Gear Housing Anodic Plates ............................. 15
Ventilation Plate Anode .................................... 15
Trim Cylinder Anodes ........................................ 15
Propeller Shaft Anode ....................................... 15
Features and Controls.............................................. 16
Remote Controls................................................ 16
Power Trim ........................................................ 16
Stern-Drive Trim Angle ...................................... 17
Trim and Tilt/Trailering Switch ........................... 17
Electrical System ............................................... 18
Yanmar Cathodic Protection System................. 19
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TABLE OF CONTENTS
ii ZT370 Operation Manual
Stern-Drive Operation................................................... 21
Propeller Selection ................................................... 22
Installing the Propellers ............................................ 23
Removing the Propeller ............................................ 25
Daily Checks............................................................. 25
Visual Checks .................................................... 25
Check the Stern-Drive Oil Level......................... 26
Check the Power Trim Pump Fluid .................... 27
Maintenance .................................................................. 29
Periodic Maintenance ............................................... 30
The Importance of Periodic Maintenance .......... 30
Performing Periodic Maintenance ...................... 30
The Importance of Daily Checks ........................ 30
Yanmar Replacement Parts ............................... 30
Tools Required................................................... 30
Ask Your Authorized Yanmar Marine Dealer
or Distributor for Help ......................................... 30
Tightening Fasteners................................................ 31
Torque Charts........................................................... 31
Standard Torque Values .................................... 31
Torque Specifications......................................... 31
Periodic Maintenance Table ..................................... 32
General Inspection ................................................... 34
Power Trim Pump Fluid ............................................ 34
Periodic Maintenance Procedures............................ 35
Weekly ............................................................... 35
After Initial 50 Hours of Operation...................... 36
Every 50 Hours of Operation.............................. 37
Every 100 Hours of Operation............................ 37
Every 150 Hours of Operation............................ 40
Every 250 Hours of Operation............................ 41
Every 1000 Hours of Operation.......................... 46
Every Year ......................................................... 47
Every 2 Years..................................................... 48
Troubleshooting............................................................ 49
Long-Term Storage....................................................... 51
Cold Weather (Freezing Temperature),
Seasonal and Extended Storage.............................. 51
Stern-Drive Lay Up............................................. 51
Stern-Drive Recommissioning............................ 52
Specifications................................................................ 53
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ZT370 Operation Manual 1
ZT370 Operation Manual
INTRODUCTION
Welcome to the world of Yanmar Marine!
Yanmar Marine offers engines, stern-drive
systems and accessories for all types of
vessels, from runabouts to sailboats, and
from cruisers to mega yachts. In marine
leisure boating, the worldwide reputation of
Yanmar Marine is second to none.
Yanmar stern-drives are designed for a
wide range of applications and are
designed to reduce vibration and make
your cruising more pleasurable.
To help you enjoy your Yanmar Marine
products for many years to come, please
follow these recommendations:
• Read and understand this Operation
Manual before you operate your vessel
to ensure that safe operating practices
and maintenance procedures are
followed.
• Keep this Operation Manual in a
convenient place for easy access.
• If this Operation Manual is lost or
damaged, order a new one from your
authorized Yanmar Marine dealer or
distributor.
• Make sure this manual is transferred to
subsequent owners. This manual should
be considered a permanent part of the
vessel and remain with it.
• Constant efforts are made to improve the
quality and performance of Yanmar
products, so some details included in
this Operation Manual may differ slightly
from your stern-drive. If you have any
questions about these differences,
please consult your authorized Yanmar
Marine dealer or distributor.
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INTRODUCTION
2ZT370 Operation Manual
RECORD OF OWNERSHIP
Take a few moments to record the information you need when you contact Yanmar for
service, parts or literature.
Stern-Drive Model:_______________________________________________________
Stern-Drive Transom Assembly Serial No.:___________________________________
Stern-Drive Unit Serial No.:________________________________________________
Stern-Drive Gear Ratio: ___________________________________________________
Date Purchased:_________________________________________________________
Engine Model: __________________________________________________________
Engine Horsepower: _____________________________________________________
Propeller Number: _______________________________________________________
Propeller Pitch: _________________________________________________________
Propeller Diameter: ______________________________________________________
Hull Identification Number (HIN): ___________________________________________
Boat Manufacturer: ______________________________________________________
Boat Model: ____________________________________________________________
Dealer:_________________________________________________________________
Dealer Phone:___________________________________________________________
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ZT370 Operation Manual 3
ZT370 Operation Manual
SAFETY
Yanmar considers safety of great
importance and recommends that anyone
that comes into close contact with its
products, such as those who install,
operate, maintain or service Yanmar
products, exercise care, common sense
and comply with the safety information in
this manual and on the engine and
stern-drive’s safety labels. Keep the labels
from becoming dirty or torn and replace
them if they are lost or damaged. Also, if
you need to replace a part that has a label
attached to it, make sure you order the
new part and label at the same time.
DANGER
DANGER indicates a hazardous
situation which, if not avoided, will
result in death or serious injury.
WARNING
WARNING indicates a hazardous
situation which, if not avoided, could
result in death or serious injury.
CAUTION
CAUTION indicates a hazardous
situation which, if not avoided, could
result in minor or moderate injury.
NOTICE
NOTICE indicates a situation which can
cause damage to the machine, personal
property and/or the environment or cause
the equipment to operate improperly.
A
This safety alert symbol
appears with most safety
statements. It means
attention, become alert,
your safety is involved!
Please read and abide by
the message that follows
the safety alert symbol.
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SAFETY
4ZT370 Operation Manual
SAFETY PRECAUTIONS
General Information
There is no substitute for common sense
and careful practices. Improper practices
or carelessness can cause burns, cuts,
mutilation, asphyxiation, other bodily injury
or death. This information contains general
safety precautions and guidelines that
must be followed to reduce risk to personal
safety. Special safety precautions are
listed in specific procedures. Read and
understand all of the safety precautions
before operation or performing repairs or
maintenance.
Before You Operate
WARNING
• Never permit anyone to
install or operate the
engine or stern-drive
without proper training.
• Read and understand this Operation
Manual before you operate or service
the engine or stern-drive to ensure
that you follow safe operating
practices and maintenance
procedures.
• Safety signs and labels are additional
reminders for safe operating and
maintenance techniques.
• Consult your authorized Yanmar
Marine dealer or distributor for
additional training.
During Operation and
Maintenance
DANGER
Fire Hazard
Ensure that appropriate
fire detection and
extinguishing equipment
are installed and checked
periodically for proper
operation.
Crush Hazard
• Always use lifting
equipment with
sufficient capacity to lift
the stern-drive.
• Never stand under a hoisted
stern-drive. If the hoist mechanism
fails, the stern-drive will fall on you,
causing serious injury or death.
• Never support the stern-drive with
equipment not designed to support
the weight of the stern-drive such as
wooden pieces, blocks or by only
using a jack.
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SAFETY
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ZT370 Operation Manual 5
WARNING
Explosion Hazard
While the engine is
running or the battery is
charging, hydrogen gas is
being produced and can
be easily ignited. Keep the
area around the battery
well-ventilated and keep sparks, open
flame and any other form of ignition out
of the area.
Fire Hazard
Undersized wiring
systems can cause an
electrical fire.
Sever Hazard
• Never service the
stern-drive while under
tow or if the engine is
running at idle speed.
The propeller may rotate
under these
circumstances.
• If the vessel has more than one
engine, never service a stern-drive if
either of the engines are running. In
multi-engine configurations, the
propeller for an engine that is shut
down may rotate if any of the other
engines are running.
WARNING
(Continued)
• Rotating parts can cause severe
injury or death. Never wear jewelry,
unbuttoned cuffs, ties or loose-fitting
clothing, and always tie long hair
back when working near
moving/rotating parts such as the
flywheel or PTO shaft. Keep hands,
feet and tools away from all moving
parts.
• To prevent accidental equipment
movement, never start the engine in
gear.
• Before starting the engine, always
make sure that all bystanders are
clear of the area. Keep children and
pets away while the engine is
operating.
• Always remove any tools or shop
rags used during maintenance from
the area before operation.
• Stop the engine before you begin to
service the stern-drive and secure the
propeller so it will not turn.
Alcohol and Drug Hazard
Never operate the engine
while under the influence
of alcohol or drugs or
when feeling ill.
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SAFETY
6ZT370 Operation Manual
WARNING
Exposure Hazard
Always wear personal
protective equipment
including appropriate
clothing, gloves, work
shoes, eye and hearing
protection as required by
the task at hand.
Entanglement Hazard
• Never leave the key in
the key switch when
servicing the engine or
stern-drive. Someone
may accidentally start
the engine and not
realize you are servicing
it.
• Never operate or service the engine
while wearing a headset to listen to
music or the radio because it will be
difficult to hear the warning signals.
Burn Hazard
Some of the engine and
stern-drive surfaces
become very hot during
operation and shortly after
shutdown. Keep hands
and other body parts away
from hot surfaces.
WARNING
Exhaust Hazard
• Never block windows,
vents, or other means of
ventilation if the engine
is operating in an
enclosed area.
• All internal combustion engines
create carbon monoxide gas during
operation and special precautions are
required to avoid carbon monoxide
poisoning.
Electrical Shock Hazard
• Always turn off the
battery switch (if
equipped) or disconnect
the negative battery
cable before servicing
the equipment.
• Always keep the electrical connectors
and terminals clean. Check the
electrical harnesses for cracks,
abrasions, and damaged or corroded
connectors.
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SAFETY
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ZT370 Operation Manual 7
CAUTION
Poor Lighting Hazard
Ensure that the work area is adequately
illuminated. Always install wire cages
on portable safety lamps.
To o l H a z a rd
Always use tools appropriate for the
task at hand and use the correct size
tool for loosening or tightening
machine parts.
Flying Object Hazard
Always wear eye
protection when servicing
the stern-drive or when
using compressed air or
high-pressure water. Dust,
flying debris, compressed
air, pressurized water or steam may
injure your eyes.
Slipping and Tripping Hazard
• Ensure that adequate
floor space is set aside
for servicing the
stern-drive. The floor
space must be flat and
free of holes.
• Keep the floor free of dust, mud,
spilled liquids and parts to help
prevent slipping and tripping.
NOTICE
It is important to perform the daily checks
as listed in this Operation Manual.
Periodic maintenance prevents
unexpected downtime, reduces the
number of accidents due to poor engine or
stern-drive performance and can help
extend the life of the engine and
stern-drive.
Always be environmentally
responsible.
Follow the guidelines of the EPA or other
governmental agencies for the proper
disposal of hazardous materials such as
lubrication oil, diesel fuel and engine
coolant. Consult the local authorities or
reclamation facility.
Never dispose of hazardous materials by
dumping them into a sewer, on the ground
or into ground water or waterways.
Before operating the engine, check
stern-drive oil level.
If the stern-drive oil temperature is too
high, stop engine immediately and check
the stern-drive oil level and check the oil
cooler for proper coolant and water flow.
Always tighten components to the
specified torque. Loose parts can cause
equipment damage or cause it to operate
improperly.
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SAFETY
8ZT370 Operation Manual
NOTICE
Only use replacement parts specified.
Other replacement parts may affect
warranty coverage.
Never attempt to modify the stern-drive’s
design or safety features.
Failure to comply may impair the
stern-drive’s safety and performance
characteristics and shorten the
stern-drive’s life. Any alterations to this
stern-drive may affect the warranty
coverage of your stern-drive.
Never use the stern-drive lifting eye to lift
the engine and stern-drive as an
assembly. Use the engine lifting eyes to lift
the engine and stern-drive. Only use the
stern-drive lifting eye to lift the stern-drive
as a separate component.
The anode of the stern-drive is only
calculated for the stern-drive. Changing
the material of the propeller may require
additional anodes to be installed on the
stern-drive.
Anytime the boat is left in the water and
the engine is not running, the drive must
be left in the fully down position. This will
keep the anodes in the water and will keep
the exhaust pipe engaged with the exhaust
port of the drive.
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ZT370 Operation Manual 9
ZT370 Operation ManualPRODUCT
OVERVIEW
OVERVIEW
Owner/Operator Responsibilities
The operator must, and assumes all
responsibility to:
• Read and understand the operation
manual prior to operating the stern drive;
• Perform all safety checks as necessary
to ensure safe operation;
• Comply with and follow all lubrication
and maintenance instructions and
recommendations; and
• Have an authorized Yanmar Marine
dealer/distributor perform periodic
checkups.
Conducting normal maintenance service
and replacing consumable parts as
necessary is the responsibility of the
owner/operator and necessary to provide
the best durability, performance and
dependability of the stern drive while
keeping your overall operating expenses
to a minimum. Individual operating habits
and usage may increase the frequency of
performing maintenance service condition.
Monitor conditions frequently to determine
if the maintenance intervals suggested in
the manual are frequent enough for stern
drive.
NOTICE
The anode of the stern-drive is only
calculated for the stern-drive. Changing
the material of the propeller may require
additional anodes to be installed on the
stern-drive.
New Stern-Drive Break-In:
• On the initial engine start-up, allow the
engine to idle for approximately 15
minutes while you check for proper
stern-drive function and stern-drive oil
leaks.
• During the break-in period, carefully
observe stern-drive indicators (if any) for
proper stern-drive function.
• During the break-in period, check the
stern-drive oil levels frequently.
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PRODUCT OVERVIEW
10 ZT370 Operation Manual
Dealer/Distributor
Responsibilities
In general, a dealer’s responsibilities to the
customer include predelivery inspection
and preparation such as:
• Ensure that the vessel is properly
equipped.
• Prior to delivery, make certain that the
Yanmar stern-drive and other equipment
are in proper operating condition.
• Make all necessary adjustments for
maximum efficiency.
• Familiarize the customer with the
on-board equipment.
• Explain and demonstrate the operation
of the stern-drive and vessel.
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PRODUCT OVERVIEW
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ZT370 Operation Manual 11
COMPONENT IDENTIFICATION
Figure 1
039031-00E01
Steering system
location
Transom assembly
Drive unit
Antiventilation
plate
Trim cylinder
Y-CaPS electrode
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PRODUCT OVERVIEW
12 ZT370 Operation Manual
Location of Serial Numbers
The serial numbers are the manufacturer’s keys to numerous engineering details which
apply to your Yanmar stern-drive. When contacting Yanmar about service, always
specify model and serial numbers.
Figure 2
039032-00E00
Transom assembly serial number
Drive unit
serial
number
039033-00E00
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PRODUCT OVERVIEW
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ZT370 Operation Manual 13
CORROSION PROTECTION
Galvanic Corrosion
Galvanic corrosion results whenever two
or more dissimilar metals (like those found
on the stern-drive) are submerged in a
conductive solution, such as saltwater,
polluted water or water with a high mineral
content because a chemical reaction takes
place causing electrical current to flow
between the metals. The electrical current
flow causes the metal that is most
chemically active, or anodic, to erode. If
not controlled, galvanic corrosion may
corrode stern-drive components.
NOTICE
The anode of the stern-drive is only
calculated for the stern-drive. Changing
the material of the propeller may require
additional anodes to be installed on the
stern-drive.
Corrosion Control
It is the boat designer’s responsibility
and/or the re-powering engineer’s
responsibility to design the proper systems
and equipment to control and reduce the
possibility of galvanic corrosion.
To help control the effects of galvanic
corrosion, Yanmar Marine ZT370
stern-drives come with several anodes and
an electronic anticorrosion system
(Y-CaPS) that protect the stern-drive in
moderate corrosive conditions. However, it
is essential that the owner/operator
frequently monitor the anodes for wear,
inspect the stern drive for corrosion and
replace the anodes often enough to
provide a sacrificial surface for the
electrical current to attack. Galvanic
isolators are also available from the
aftermarket (not supplied by Yanmar) to
block stray current while still providing a
path to ground for dangerous shock
currents.
The rate of corrosion depends on
numerous factors, such as:
• The number, size and location of anodes
on the stern-drive and vessel;
• The marina environment such as stray
current in the water, fresh or salt water
and use and isolation of shore power;
• Improper application of marine paint or
antifouling paint;
• Failure to repaint damaged areas; and
• How the vessel is bonded.
Please check with the boat builder, dealer
or other professional to determine if your
vessel and/or stern drive is adequately
protected from galvanic corrosion.
If anodes erode quickly or if signs of
corrosion are evident, the owner should
take immediate corrective action. Yanmar
recommends consulting an engineer
specializing in marine electricity and
corrosion control to determine the best
way to correct the rapid erosion of the
anodes.
Shore Power
Vessels that are connected to shore power
require additional protection to prevent
destructive low voltage galvanic currents
from passing through the shore power
ground wire. Galvanic isolators are
available from the aftermarket (not
supplied by Yanmar) to block these
currents while still providing a path to
ground for dangerous shock currents.
NOTICE
If the AC shore power ground is not
isolated from the boat ground, the Y-CaPS
and anodes may be unable to neutralize
the increased galvanic potential. Corrosion
damage that results from the improper
system design or application is not
covered by the Yanmar limited warranty.
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PRODUCT OVERVIEW
14 ZT370 Operation Manual
Underwater Drive Coating
The lower gear case coating may be
damaged when hit by objects in the water,
or when having deposits removed from it.
The underwater coating must be inspected
at least once per year and when it is
believed that an object was hit that may
have caused damage. Repair and repaint
damaged areas immediately.
Observe the following precautions when
applying antifouling or marine paint to the
transom of the boat hull:
• Always follow the paint/coating
manufacturer’s directions for surface
preparation and application.
• Always use a high quality primer and
topcoat paint specifically designed for
aluminum outboards or stern-drives.
• Never paint the anodes installed on the
stern-drive.
• Never paint the Y-CaPS reference
electrode and/or anode.
• Never wash the stern-drive with a high
pressure washer. This could damage the
coating on the reference wire.
• Never paint the stern-drive with a
material that contains copper or tin.
• Never paint over drain holes, anodes,
Y-CaPS or other items specified by the
anode manufacturer.
Consult your authorized Yanmar Marine
dealer or distributor for assistance.
NOTICE
Galvanic corrosion damage, normal
maintenance and consumable parts are
not covered by the Yanmar limited
warranty.
Additional Protection
In addition to the corrosion protection
devices, take these steps to inhibit
corrosion:
1. Paint the stern-drive. See Touching-up
the stern-drive paint and spray with
corrosion guard on page 41.
2. Spray stern-drive components on the
inside of the vessel annually with
corrosion guard to protect the finish
from dulling and corrosion. External
stern-drive components may also be
sprayed.
3. Keep all lubrication points, especially
the steering system, shift and throttle
linkages, well-lubricated.
4. Flush the coolant system periodically,
preferably after each use.
NOTICE
Replace anodes if eroded 50 percent or
more.
NOTICE
Anytime the boat is left in the water and
the engine is not running, the drive must
be left in the fully down position. This will
keep the anodes in the water and will
keep the exhaust pipe engaged with the
exhaust port of the drive.
Figure 3
039030-00E00
Trim cylinder anodes
Y-CaPS
electrode
Ventilation
plate anode
Propeller shaft
anodes
Gear
housing
anodic
plates
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PRODUCT OVERVIEW
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ZT370 Operation Manual 15
Gear Housing Anodic Plates
The gear housing anodic plates
(1, Figure 4) are installed on the
underside of the antiventilation plate.
Figure 4
Ventilation Plate Anode
The ventilation plate anode (1, Figure 5) is
installed on the front of the drive shaft
housing on top of the ventilation plate.
Figure 5
Trim Cylinder Anodes
The trim cylinder anodes (1, Figure 6) are
installed on each trim cylinder.
Figure 6
Propeller Shaft Anode
The propeller shaft anode (1, Figure 7) is
located behind the aft propeller.
Figure 7
039037-00X00
1
039034-00X00
1
039035-00X00
1
039036-00X00
1
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PRODUCT OVERVIEW
16 ZT370 Operation Manual
FEATURES AND CONTROLS
Remote Controls
The Yanmar ZT370 can be controlled mechanically with push-pull cables or electronically.
Please refer to the Yanmar Engine Operation Manual or the Electronic Control System
Operation Manual (if so equipped).
Power Trim
The power trim is used to accelerate the vessel onto plane, reach the desired engine rpm
or vessel speed, and improve the performance of the vessel when there is a change in
water or boating conditions. The performance of the vessel depends on load weight and
distribution. Distribute the weight evenly, from bow to stern and from port to starboard.
Trimming will not improve the vessel’s performance due to an imbalanced load.
Figure 8
Figure 9
Figure 10
039047-00X00
039048-00X00
039049-00X00
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