YAMARIN 53 Bow Rider User manual

YAMARIN 53 Bow Rider 1 (36)
YAMARIN 53 Bow Rider
OWNER’S MANUAL

YAMARIN 53 Bow Rider 2 (36)
FOREWORD
Dear Owner of the Finnish Yamarin-boat! We thank you for choosing Yamarin and wish you
many pleasant experiences while on the water.
The intention of this manual is to help you to operate your craft with safety and pleasure. It
contains details of the craft, the equipment supplied or fitted, its systems and information on
its operation, care and maintenance. Please read it carefully, and familiarise yourself with the
craft before using it.
Naturally, owner's manual is not a course on boating safety or seamanship. If this is your first
craft, or you are changing to a type of craft you are not familiar with, for your own comfort
and safety, please ensure that you obtain handling and operating experience before "assuming
command" of the craft. Your dealer or national sailing federation or yacht club will be pleased
to advise you of local sea schools, or competent instructors.
Ensure that the anticipated wind and sea conditions will correspond to the design category of
your craft, and that you and your crew are able to handle the craft in these conditions.
The sea and wind conditions corresponding to the design categories A, B, and C range from
severe storm conditions to strong conditions, and are open to the hazards of a freak wave or
gust. Even when your boat is categorised for them, they are dangerous conditions, where only
a competent, fit and trained crew using a well maintained craft can satisfactorily operate.
This owner's manual is not a detailed maintenance or trouble shooting guide. In case of
difficulty, refer to the manufacturer or his representative. Always use trained and competent
people for maintenance, fixing or modifications. Modifications that may affect the safety
characteristics of the craft shall be assessed, executed and documented by competent people.
The manufacturer cannot be held responsible for modifications he has not approved.
In some countries a driving licence or authorisation are required, or specific regulations are in
force.
Always maintain your craft properly and make allowance for the deterioration that will occur
in time and as a result of heavy use or misuse of the craft.
Any craft – no matter how strong it may be, can be severely damaged if not used properly.
This is not compatible with safe boating. Always adjust the speed and direction of the craft to
sea conditions.

YAMARIN 53 Bow Rider 3 (36)
If your craft is fitted with a life raft, read carefully its operating manual. The craft should have
onboard the appropriate safety equipment (lifejackets, harness, etc.) according to the type of
craft, weather conditions, etc., these equipments are mandatory in some countries. The crew
should be familiar with the use of all safety equipment and emergency manoeuvring (man
overboard recovery, towing, etc). Sailing schools and clubs regularly organise drill sessions.
All persons should wear a suitable buoyancy aid (Life jacket/Personal Floatation Device)
when on deck. Note that in some countries it is a legal requirement to wear a buoyancy aid
that complies with their national regulations at all times
We wish you lots of fun and hope you have a good time on board your YAMARIN!
KoneKesko Marine
P.O.B. 145
FIN-01301 VANTAA
Telephone [phone]
www.kesko-marine.com
www.yamarin.com
PLEASE KEEP THIS MANUAL IN A SECURE PLACE, AND HAND IT OVER TO THE
NEW OWNER IF YOU SELL THE CRAFT."

YAMARIN 53 Bow Rider 4 (36)
Sisällysluettelo
1 General 7
1.1 Declaration of confirmity 7
2 Definitions 12
3 Warranty 12
4 Before use 12
4.1 Registering 12
4.2 Insurances 12
4.3 Training 13
5 Characteristics and use of your boat 13
5.1 General 13
5.2 Basic data 13
Specifications 15
5.3 Maximum number of persons 16
5.4 Loading 16
5.5 Engine and propeller 16
5.6 Risk of flooding and stability 17
5.6.1 Openings in the hull and deck 17
5.6.2 Stability and buoyancy 18
5.7 Risk of fire or explosion 18
5.7.1 Refuelling 18
5.7.2 Fire protection 19
5.8 Main switch 19
5.9 Operation 20
5.9.1 Controls 20
5.9.2 Emergency switch 20
5.9.3 Gearshift and throttle 20
5.9.4 Adjusting the trim angle 21
5.9.5 Starting the engine 21
5.9.6 Driving 21
5.9.7 Approaching the dock 22
5.9.8 Use of canopy 23
5.10 Proper use – other recommendations and guidelines 23
5.10.1 Man-overboard prevention and recovery 23
5.10.2 Securing of loose equipment 23
5.10.3 Respect for environment 24
5.10.4 Anchoring, mooring and towing 24
5.10.5 Towing 25
5.10.6 Trailer transport 25
5.10.7 Docking 26
6 Maintenance of boat and equipment 28

YAMARIN 53 Bow Rider 5 (36)
6.1 Washing and waxing the boat 28
6.2 Care instructions for seat cushions 28
6.3 Care instructions for canopy 29
6.4 Care instructions for windshield 29
6.5 Care instructions for remote control 29
6.6 Care instructions for steering system 29
6.7 Care instructions for electrical components 29
6.8 Minor superficial repairs 30
7 Winter storage 30
7.1 Measures before winter storage 31
7.2 Measures before launching 32
8 Lay-out 33
8.1 General arrangement 33
8.2 Fuel system 34
8.3 Steering system 34
8.4 Electrical system 35
8.5 Wiring diagram 36

YAMARIN 53 Bow Rider 6 (36)
BEFORE YOU START
Familiarise yourself with this owner’s manual.
Always check at least the following items before leaving:
−
−−
− Weather state and forecast
Take the wind, waves and visibility into account. Are the design category, size and
equipment of your boat, as well as the skills of the skipper and crew adequate for the
water area you are aiming to? In high wind and waves the hatches must be closed to
prevent water ingression
−
−−
− Loading
Do not overload the craft, distribute loads appropriately. To avoid impairment of the
stability, do not place heavy weights high up.
−
−−
− Passengers
Ensure that there is lifejackets for all people on board. Agree about the crew tasks before
leaving.
−
−−
− Fuel
Check that there is enough fuel, also reserve 20 % for bad weather etc.
−
−−
− Engine and equipment
Check function and condition of steering, electric equipment and battery, and do the
routine checks required by the owner’s manual of the engine. Check the seaworthiness in
other aspects also: no leaks of fuel or water, safety equipment on board etc. Check that
bilge water is at a minimum.
−
−−
− Ventilation
Take care of tank compartmets ventilation.
−
−−
− Fastening of equipment
Check that all equipment and heavy items are positioned so that they hold in place also in
seaway and hard wind.
−
−−
− Nautical charts
If you are not navigating on totally familiar waters, do you have on board nautical charts
covering an area large enough?
−
−−
− Leaving the berth
Agree with the crew, who will release each mooring line etc. Be careful not to let mooring
lines or other ropes to entangle the propeller during manoeuvring.
- Obligatory equipment
Each country has different regulations. Find out what are the needs in Your own area.
You will find additional instructions concerning the engine from its separate manual.
Own notes

YAMARIN 53 Bow Rider 7 (36)
1General
The Owner’s manual will help you to familiarise with the properties and features of your new
boat, as well as with its care and maintenance. Separate manuals of the installed equipments
are attached and are referred to in many sections. You can of course complement this owner’s
manual by adding the manuals of the devices which are installed afterwards. There is also
space for your own notes in the end of this manual.
The craft has a running serial number, CIN-code. The CIN-code is labelled on the hull of the
craft on the aft part at right side / on outer surface of transom beneath the edge rail. You can
write down the relevant CIN-code in the declaration of confirmity. When you have affairs
with the manufacturer or dealer, please tell the CIN-code and the type of craft. This helps in
delivering correct spare parts. If you need gelcoat for repairs, tell the code of the relevant
colour when ordering.
1.1 Declaration of confirmity

YAMARIN 53 Bow Rider 8 (36)
DECLARATION OF CONFIRMITY
Recreational Craft • Directive 94/25/EC
Manufacturer: See CIN-code and manufacturer list
Module used (check):
-----------------------------------------------------------------------------------------------------------------
THE DECLARATION IS PLACED ON THE MARKET BY
Placed on the market by: Konekesko Oy Marine
Address: Vanha Porvoontie 245
Zip code: 01380 City:Vantaa
Land: (code):FIN (printed): SUOMI, FINLAND
-----------------------------------------------------------------------------------------------------------------
NOTIFIED BODY
Name:VTT-Tuotteet ja Tuotanto Identification number: 0537
Address: PL1705
Zip code:FIN 02044 VTT City:
Land: (code) FIN (printed) SUOMI, FINLAND
If EC type-examination certificate has been issued (certificate number and date yr/mo/day) 322/1B1/2000, xx / xx / xx
-----------------------------------------------------------------------------------------------------------------
DESCRIPTION OF THE CRAFT
Hull identification number (CIN):
Brand name of the craft: YAMARIN
Type or number: 53 Bow Rider
Design category: C
Type of craft *: 03
Type of hull *: 01
Deck *: 03
Construction material *: 02
Propulsion *: 02
Type of engine *: 01
Maximum recommended engine power (kW): 73,6
Length and beam of hull (m): 5,19/2,20
Draught (m):
* codes on opposite side
I declare at my own and sole responsability that the craft mentioned above complies with all
applicable essential requirements in the way specified overleaf (and is in conformity with
the type for which above mentioned EC type examination certificate has been issued –
include only if such certificate has been issued).
A - Aa - B+C X B+D - B+F - G - H -
-

YAMARIN 53 Bow Rider 9 (36)
Name: Peter Krusberg
The person empowered to sign
Product Manager
Date (yr/mo/day): 2005 / 01 / 27
Type of craft: Deck:
01 sailboat 01 decked
02 inflatable 02 partly decked
03 other: motorboat 03 open:
Type of hull: Propulsion:
01 monohull 01 sails
02 multihull 02 petrol engine
03 other: 03 diesel engine
04 electrical motor
05 oars
06 other:
Construction material: Type of engine:
01 aluminium, aluminium alloys 01 outboard
02 plastic, fiber reinforced plastic 02 inboard
03 steel, steel alloys 03 z or sterndrive
04 wood 04 other:
05 other:

YAMARIN 53 Bow Rider 10 (36)
Essential requirements ISO-standards used Other normative document used
General requirements (2)
Hull Identification Number – CIN (2.1) ISO 100087
Builder’s Plate (2.2) ISO 11592 RSG Gguidelines
Protection from falling overboard and means of reboarding …
(2.3)
RSG Gguidelines
Visibility from the main steering position (2.4) RSG Gguidelines NBS F10
Owner’s manual (2.5) ISO 10240
Structure (3.1) RSG Gguidelines, NBS-VTT Extended
rule
Stability and freeboard (3.2) ISO 12217 RSG Gguidelines, NBS F3
Buoyancy and floatation (3.3) ISO 12217 RSG Gguidelines, NBS F12
Openings in hull, deck and superstructure (3.4) ISO 9093, ISO 12216 RSG Gguidelines
Flooding (3.5) ISO 11812, ISO 12216, ISO 12217, ISO 8849 RSG Gguidelines
Manufacturer’s maximum recommended load (3.6) ISO 12217 RSG Gguidelines, NBS F3
Liferaft stowage (3.7) RSG Gguidelines
Escape (3.8) ISO 9094 RSG Gguidelines
Anchoring, mooring and towing (3.9) RSG Gguidelines
Handling characteristics (4) ISO 8665, ISO11592 RSG Gguidelines
Asennusvaatimukset (5)
Engines and engine spaces (5.1) ISO 11105, ISO 9094 RSG Gguidelines
Inboard engine (5.1.1)
Ventilation (5.1.2)
Exposed parts (5.1.3)
Outboard engine starting (5.1.4)
Fuel system (5.2) ISO 10088, ISO 11105, ISO 9094 RSG Gguidelines
General – fuel system (5.2.1)
Fuel tanks (5.2.2)
Electrical systems (5.3) ISO 10133, ISO 13297 RSG Gguidelines
Steering systems (5.4) ISO 8848, ISO 10592, ISO 9775, ISO 13929
General – steering system (5.4.1)
Emergency arrangements (5.4.2)
Gas systems (5.5) ISO 10239
Fire protection (5.6) ISO 9094 RSG Gguidelines
General – fire protection (5.6.1)
Fire-fighting equipment (5.6.2)
Navigation lights (5.7) 1972 COLREG
Discharge prevention (5.8) ISO 8099 RSG Gguidelines

YAMARIN 53 Bow Rider 11 (36)
MANUFACTURER LIST
1.Fenix Marin Oy
Lujatie 2
14500 Iittala , Suomi Finland
CIN: FIFNX
2. Seliö Boats Oy
Yrittäjäntie 4
09220 SAMMATTI , Suomi Finland
CIN: FISEL
3.Saint Boats Ky
Wattitie 3
21530 Paimio , Suomi Finland
CIN: FISAB & 74C FIYAM
4.Esmarin Oy
Tuottajantie 1
57230 Savonlinna , Suomi Finland
CIN: FIESM
5.Oy Finn-Marin Ltd
Kölitie 3
67900 Kokkola , Suomi Finland
CIN: FIFMN

YAMARIN 53 Bow Rider 12 (36)
2Definitions
The warnings and cautions in this manual are defined as following:
DANGER! Denotes an extreme intrinsic hazard exists which would result in high
probability of death or irreparable injury if proper precautions are not
taken.
WARNING! Denotes a hazard exists which can result in injury or death if proper
precautions are not taken.
CAUTION! 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.
The units used in this manual are in accordance with SI-system. In some cases other units has
been added in brackets. An exception is the wind speed, where Beaufort scale is used in the
recreational craft directive.
3Warranty
The boat and the equipment installed at the boatyard are guaranteed for one year according to
the attached warranty clauses. Motor, isntruments and other devices are guaranteed directly
by their manufacturers:
Please contact your dealer when need information of the warranty. When discoussing about
warranty, please announce your boat-model and 'CIN code' (identification number). The
boat's identification number is located on the right side of the transom, below the rubbing
strake
4Before use
4.1 Registering
Each country has different regulations. Find out what are the needs in Your own area.
4.2 Insurances
Boat insurance can compensate damage occurring on water or during transport. Assure
insurance liability separately when lifting the boat. Insurance has also an indirect effect to
safety at sea: In case of serious accident or damage, you can above all concentrate on saving
the persons. The insurance companies are pleased to give more information about the
insurance conditions. Each country has different regulations. Find out what are the needs in
Your own area.

YAMARIN 53 Bow Rider 13 (36)
4.3 Training
It is advisable to practice boat handling. There is plenty of boating literature available.
Navigation courses are arranged by local yacht clubs or authorities.
Each country has also different regulations. Find out what are the needs for training in Your
own area.
However, you only become confident in boat handling, navigating, docking and anchoring
after long practical experience.
5Characteristics and use of your boat
5.1 General
The meaning of the Owner’s manual is not to be a complete service or repair manual, but to
guide the user to know the charateristics of the boat and to use his/her boat in a proper way.
5.2 Basic data
Manufacturer:Konekesko Oy, Marine P.O.B.145 FIN-01301 VANTAA, Tel [phone]
Design category: ABCD
Design category is explained as follows:
Category A:This craft is designed to operate in winds that may exceed wind
force 8 (Beaufort scale) and in significant wave heights of 4 m and above (see
note below), and vessels largely self-sufficient. Abnormal conditions such as
hurricanes are excluded. Such conditions may be encountered on extended
voyages, for example across oceans, or inshore when unsheltered from the wind
and waves for several hundred nautical miles.
Category B: This craft is designed to operate in winds up to Beaufort force 8
and the associated wave heights (Significant wave height up to 4 m, see note
below). Such conditions may be encountered on offshore voyages of sufficient
length or on coastal waters when unsheltered from the wind and waves for
several dozens of nautical miles. These conditions may also be experienced on
inland seas of sufficient size for the wave height to be generated.
Category C: This craft is designed to operate in winds up to Beaufort force 6
and the associated wave heights (Significant wave height up to 2 m, see note
below). Such conditions may be encountered on exposed inland waters, in
estuaries, and in coastal waters in moderate weather conditions.
Category D: This craft is designed to operate in winds up to Beaufort force 4
and the associated wave heights (Occasional maximum waves of 0,5 m height).
Such conditions may be encountered on sheltered inland waters, and in coastal
waters in fine weather.

YAMARIN 53 Bow Rider 14 (36)
Note: The significant wave height is the mean height of the highest one third of the waves,
which approximately corresponds to the wave height estimated by an experienced observer.
Some waves will be double this height.
Maximum recommended load: See specifications
See also section 5.4 ”Loading”
Main dimensions and capacities:See specifications
Craft length, breadth, draft, total weight etc. as well as tank capacities are shown
in specifications.
Range of use: See design category
Your boat’s desing category is shown in specifications.
Builder’s plate:
Part of the information is given on the builder's plate, which is affixed next to
remote control. A full explanation of this information is given in the relevant
sections of this manual.

YAMARIN 53 Bow Rider 15 (36)
Specifications
Boat model YAMARIN 53 Bow Rider
Design category C
Length overall 5,19m
Maximum width 2,20m
Weight without
engine, fluids and
equipment
600kg
Maximum load /
persons
525kg/ 7 +fuel 70kg +equipment 10kg
Maximum load in
builders plate
535kg
Maximum engine
power
73,6kW/ 100hv
Maximum
recommended weigh
of engine
190kg
Fuel tank capacity 90litres
Material Polyester resin/reinforced glass fibre
Colour codes:
-Hull
-Deck
-Blue stripe
Ashland 10015 RAL 9016
Ashland 10015 RAL 9016
Ashland 39500 RAL 5011
Water line:
-At stern
-At bow
80 mm
1190 mm
Remote control
cables
3,50m
Steering cable 13’ feet
Example figure, waterlines

YAMARIN 53 Bow Rider 16 (36)
5.3 Maximum number of persons
The maximum recommended number of persons on board is shown in specifications.
See general arrangement
WARNING! Do not exceed the maximum recommended number of persons.
Regardless of the number of persons on board the total weight of
persons and equipment must never exceed the maximum
recommended load (see chapter Loading). Always use the
seats/seating spaces provided.
5.4 Loading
The maximum recommended load of your boat is shown in specifications. This includes the
for example following weights:
a) the total weight of persons on board xx kg (the default mass of an adult is 75 kg and of
a child 37,5 kg)
b) basic equipment 10 kg
c) consumable liquids (fresh water, fuel etc.) in portable tanks xx kg
d) personal equipment ( e.g. hobby equipment) xx kg.
e) other stores xx kg
f) cargo (e.g. hobby equipment) xx kg
Example calculation:
Yamarin YAMARIN 53 Bow Rider, maximum recommended load = 535kg + fuel 70kg.
There is 4 adults, 2 childs, 20kg portable water tank, 10kg basic equipment and 15kg fishing
equipment on board
4x75kg + 2x37,5kg + 20kg + 10kg + 15kg = 420kg
Load on board 420kg < maximum recommended load 535kg, loading of boat is OK..
WARNING!: When loading the craft, never exceed the maximum
recommended load. Always load the craft carefully and distribute
loads appropriately to maintain design trim (approximately level).
Avoid placing heavy weights high up.
5.5 Engine and propeller
See specifications for the maximum recommended engine power and the maximum
recommended engine mass.
Follow the instructions of the engine manufacturer when choosing the propeller for your craft.

YAMARIN 53 Bow Rider 17 (36)
5.6 Risk of flooding and stability
5.6.1 Openings in the hull and deck
Yamarin boats feature a draining plug at the lower end of transom. Draining the boat on land
is done by opening the plug.
NOTE! Remember to fasten the draining plug before launching the boat.
Yamarin boats has a rainwater draining system, which means that rainwater is drained from
the undecked part of the boat when the boat is on the water. The system also functions when
the boat is out of water, provided that the bow is higher than the stern and that the rainwater
drain valve is open. See location of rainwater drin valve from your boatmodels figure.
This drain is meant to be shut at the maximum loading to prevent ingression of water. In other
loading conditions keep the drain open.
Always take along scoop and/or handpump when you are at sea.
YAMARIN 53 Bow Rider Locations of through-hull fittings and
seacocks.
WARNING! Learn to use the boat's draining systems in order to be able to use them
correctly in an emergency.
WARNING!Always keep the drainpipe shut when its inboard end is below waterline owing to
heavy load. The shut-off flap on transom only prevents water from entering the
boat when reversing!

YAMARIN 53 Bow Rider 18 (36)
NOTE! Make sure that water can flow unobstructed in the drainpipe. For instance,
autumn leaves may obstruct the water flow, which causes the undecked space
to flood, and later the bilge compartment, too.
NOTE! There is always some condensing water in the bilge. Some water may also come
through hull bushings, particularly when the boat ages. Always remember to
check the bilge before you leave the boat at quay or buoy for a longer period and
before getting underway.
WARNING! The boat's handling properties may become extremely dangerous, if there is
water in the bilge.
5.6.2 Stability and buoyancy
Please note, that stability is reduced by any weight added high up. Any change in the
disposition of the masses aboard may significantly affect the stability, trim and performance
of your craft.
YAMARIN is equipped with flotation material, which shoudn’t be reduced, by means of them
the craft floats even when swamped.
In maximum loading condition boat floats even when swamped
5.7 Risk of fire or explosion
5.7.1 Refuelling
Before you start to fill the fuel tank, turn off the engine and naturally any cigarettes. Do not
operate switches or appliances that can cause spark formation.
When filling the fuel tank, do not use a plastic funnel, which prevents discharging the
potential difference between the fuel pistol and the filling fitting. After filling (see tank
capacity in specification) check that no fuel has leaked to the bilge, and clean any spilled fuel
immediately.
Do not stow any reserve canisters in non-ventilated spaces or unsecured, or any equipment
containing petrol in spaces not intended for that.
Do not stow any loose items in the tank space, that may move and cause damage to fuel pipes
or hoses. Check annually, that the fuel hoses are not worn at lead-ins. When hose or pump is
damageg or weaken, it should be removed immediately.
WARNING! Fuel and its vapours are highly explosive. Extreme caution must be exercised
and these instructions must be followed when refuelling. The smell of fuel
always means that there is vaporised fuel in the boat.
If your boat has a teak finish and you think that fuel might splash onto it when refuelling, we
recommend that you wet the surface with water before refuelling. It prevents gasoline from
entering into wood, and no gasoline stains are left

YAMARIN 53 Bow Rider 19 (36)
5.7.2 Fire protection
When using YAMARIN with engine over 25kW (34hp), it shall be equipped with
minimum class 8A68B effect portable fire extinguisher (rating and location) shown in
your boat models figure.
YAMARIN 53 Bow Rider. Location and rating of portable fire extinguisher
The portable fire extinguishers shall be serviced annually. Over ten years old extinguishers
are not accepted without new pressure testing of the container. If you replace portable fire
extinguishers, the new ones shall have at least identical fire-fighting capacity.
Ensure that fire-fighting equipment is readily accessible also when the boat is occupied.
Inform members of the crew about the location and operation of fire-fighting equipment, the
location of discharge openings into the engine space, and the location of routes and exits.
Keep the bilges clean and check for fuel and gas vapours or fuel leaks frequently.
5.8 Main switch
Main switch (in the boat's battery compartment) operation:
- switch clockwise -> battery connected
- switch counter-clockwise -> battery disconnected
Switch off the battery when you leave the boat.
NOTE ! Never switch off the main switch when the engine is running! It may damage the
charger.

YAMARIN 53 Bow Rider 20 (36)
5.9 Operation
If this is your first boat, or a boat type new to you, take someone with experience from a
corresponding boat with you on the first times.
5.9.1 Controls
You will quickly learn how to control your YAMARIN -boat, but the ever changing weather
conditions., like wind and waves, will always present new challenges for the driver. The boat
has a cable steering system. The remote control combines the functions of throttle, forward
and reverse gears, and trim angle adjustment.
5.9.2 Emergency switch
The emergency switch is a device with one end attached to the ignition switch panel and the
other end to, for instance, your life vest. When the emergency switch is detached from the
ignition switch panel, it automatically switches off the engine. It is extremely important that
the boat stops, if, for some reason, the pilot loses his or her balance and gets thrown away
from the pilot's position. Never drive the boat without attaching the emergency switch onto
yourself. If you attach it to your arm, do not steer the boat with that hand, because the lanyard
may twine around the steering wheel in tight turns.
The engine does not start if the emergency switch is not attached to the ignition switch panel.
WARNING! A rotating propeller is dangerous to anyone fallen overboard or a swimmer.
Switch off the engine with the emergency switch or otherwise before a
swimmer or a water skier climbs on board.
5.9.3 Gearshift and throttle
The engine is put into gear by pushing the button on the gear/throttle handle upwards with
your fingers, and by pushing or pulling the gear/throttle lever forward or backward depending
on which direction you are planning to set out. When the engine is in gear, you adjust the boat
speed with this same gear/throttle lever.
When the boat is travelling forward slowly, you can use the reversing gear for braking, for
instance, when approaching the quay. Shifting into reverse must not be done if the boat is
travelling at higher speeds, because it damages the engine.