CONTENTS
INTRODUCTION
ENGINES: Cooling system
1. Engine overheating due to blockage
2. Seawater pump
Changing the impeller
Seawater pump leaking
3. Thermostat
4. Anti-syphon valve
5. Other problems
ENGINES: Fuel system
6. Fuel pump
7. Bleeding (venting) air from the fuel system
ENGINES: Electricity
8. Drive belts
ENGINES: Servicing
9. Servicing the engine
ENGINES: Other topics
10. Adjusting valve clearance
11. Engine mounts
12. Engine alignment
13. Winterisation
14. Engine won't start
15. Engine won't stop
FUEL SYSTEM
16. Fuel contamination
17. Cleaning the fuel tank
WATER SYSTEM
18. Recharging the accumulator
19. Replacing contaminated pipes
20. Hot water pressure relief valve
21. Replacing the drinking water filter
22. Installing isolation and drain valves
23. Leaking tap washer
24. Plastic water pipe fittings
25. Water pump
26. Water pump filter
GAS SYSTEM
27. Checking for leaks
28. Do I need to replace the gas system components?
29. The ideal gas system
ELECTRICAL SYSTEM
30. Formulae
31. Multimeter
32. Energy consumption
33. Batteries
34. Circuit protection
35. Connections
36. Soldering
37. Wiring
38. Troubleshooting
39. AC power
HEADS
40. Clearing blockages
41. Servicing a manual toilet pump
BILGE & WATER PUMPS
42. Whale Mk 5 / Henderson Mk IV Diaphragm Pump
43. Servicing an electric impeller pump
SEACOCKS
44. Servicing gate valves
45. Servicing ball valves
46. Servicing Blakes seacocks
STERN GEAR
47. Cutless bearing
48. Propellers
49. Sterngland
STEERING
50. Rudders
51. Wheel steering systems
ANODES
52. Changing hull anodes
53. Changing saildrive anodes
54. Changing shaft anodes
ANTIFOULING
55. Removal of old paint
56. Preparation
57. Application
58. Saildrive legs and keels
FIBREGLASS
59. Repair of puncture damage to the hull
60. Repair of stress cracking
61. Repair of cosmetic blemishes to the gelcoat
DECK HARDWARE
62. Fitting a deck vent
63. Replacing a stanchion base
LEAKS
64. Locating a leak
WINCHES
65. Winch servicing
WINDLASSES
66. Routine maintenance
INFLATABLES
67. Puncture repair
Copyright © 2014 Fernhurst Books Limited
This edition first published in 2014 by Fernhurst Books Limited
62 Brandon Parade, Holly Walk, Leamington Spa, Warwickshire CV32 4JE
Tel: +44 (0) 1926 337488
www.fernhurstbooks.com
First published in 2005 in hardback by Fernhurst Books
Reprinted in 2011 in hardback by John Wiley & Sons Ltd
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except under the terms of the Copyright, Designs and Patents Act 1988 or under the terms of a license issued by The Copyright Licensing Agency Ltd, Saffron House, 6-10 Kirby Street, London EC1N 8TS, UK, without the permission in writing of the Publisher.
Designations used by companies to distinguish their products are often claimed as trademarks. All brand names and product names used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners. The Publisher is not associated with any product or vendor mentioned in this book.
Boating and boat maintenance have inherent risks. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered. It is sold on the understanding that the Publisher is not engaged in rendering proffessional services. If professional advice or other expert assistance is required, the services of a competent professional should be sought. The Publisher accepts no responsibility for any errors or omissions, or for any accidents or mishaps which may arise from the use of this publication.
ISBN 978-1-909911-13-0 (paperback
ISBN 978-1-909911-67-3 (eBook)
ISBN 978-1-909911-68-0 (eBook)
Acknowledgments
The author would like to thank the following people and organisations for their generosity and help: Colin Bridle for allowing him to photograph the section on repairing a punctured hull.
Peter Spreadborough of Southampton Calor Centre for the use of his photographs of gas joints and fittings.
Jeff Sheddick of ITT Jabsco for supplying Jabsco products for photography.
Shamrock Chandlery for allowing him to photograph some of their stock items.
Blakes, Volvo Penta, Perkins Sabre Engines, Vetus, Lofrans and Lewmar for information, diagrams and photographs.
Photographic credits
All photographs and diagrams are by the author except:
Peter Spreadborough: pages 65-69; Blakes Lavac Taylors: page 111; Volvo Penta, diagrams and photos: pages 16, 20, 27, 38, 46, 48; Vetus: page 117; Perkins, reprinted courtesy of Perkins Engine Co. Ltd: page 25; Lewmar: pages 120, 121, 157; Lofrans: page 157; Harken: pages 1, 151
Cover design by Rachel Atkins
Design and artwork by Creative Byte & Rachel Atkins
FOREWORD
This book has been a long time in gestation, with many thoughts on the best way to present the information. Tim Davison, my publisher, has guided me and ‘Simple Boat Maintenance’ is the result.
Without my wife, Lynette, this book would not have been possible. Either her hands are shown in the photographs doing the jobs or she has taken the photographs. She has fed and watered me while I was sitting at my computer and soothed my brow when the computer was being beastly.
With this book in one hand and a spanner in the other, I hope you will enjoy trouble-free boating.
Pat Manley, Hythe, Southampton
INTRODUCTION
Lots of jobs on your boat are relatively straightforward and don’t need a great deal of skill. However, if you haven’t tackled the job before, you may not know the techniques required, or know how to set about the job.
Simple Boat Maintenance aims to talk you through much of the maintenance on your boat so that you don’t have to incur unnecessary and expensive labour charges. I have done all these jobs myself, so any of them should be within your capability. For each job the skill level required is shown on a scale of one to five to give an indication of difficulty (five is probably a job for a professional). No special tools are required.
Because there are many different products of each type on the market, I can’t show the work involved on every one of them. However, armed with Simple Boat Maintenance and the instructions that come with the product, you should be able to complete any of the work shown in this book successfully.
Jobs that require an above average level of skill are not covered in this book. But you should be able to reduce the cost of ownership and increase the level of enjoyment of owning your boat by using this book as a guide.
Each topic is covered under the following headings:
• WHY IT NEEDS TO BE DONE
• WHEN IT SHOULD BE DONE
• SKILL LEVEL REQUIRED
• TOOLS NEEDED
• WHERE TO FIND IT
• HOW TO DO IT
Sometimes a topic has information only, and in this case the page is coloured yellow.
Routine maintenance
This is carried out regularly, often on an annual basis, and doesn’t come as a surprise. You can choose when to do it, and have any tools and spares to hand ready for the job. If the boat gets a lot of use, the time interval between jobs may need to be shortened. The equipment’s instructions or handbook will tell you what’s needed and when. But do note down what you do and when you do it, maybe in the boat’s logbook. This will keep you informed and should be a good selling point if you decide to sell your boat.
Make a list of all the routine maintenance required on your boat and tick off each job as it’s done.
Mending something that has developed a fault
Sometimes it is patently obvious that something has broken and all you need to do is replace it.
At other times troubleshooting may be required to find out what’s wrong and how to cure the problem.
A philosophy of troubleshooting
When things are all right, they are NORMAL. So the first thing we need to do is to establish what this normality is. Seems simple really, doesn’t it, yet as things change slowly we may lose a sense of what is normal for that particular item. For instance: the engine may take longer to start; the genoa winch may be stiffer to operate; the helm may be heavier than it used to be.
Sometimes normality is easy to establish, such as the engine’s normal running temperature. Maybe it is normally 70°C, but we don’t have to remember this: a little paint-mark on the instrument where the needle usually resides will do the job nicely. If we have two engines, why have the temperature gauges on opposite sides of the panel? Put them next to each other and any change is obvious. Unfortunately, designers are often more interested in style rather than doing a proper job!
We need to have a feeling for what is NORMAL. This allows us to know when something has changed and it is CHANGE that tells us that something may be wrong.
Then we need to have a look at the change to see if it’s real or significant. For instance, the fact that the boat is going more slowly than usual at a given rpm doesn’t have to indicate that the engine has lost power. It may mean that the hull or propeller is fouled or even that the log impeller is fouled. So we have to look at ALL the symptoms. In this case a glance at the wake of the boat would tell us if it were a fouled impeller. The fact that the hull was last antifouled a year ago would indicate the strong likelihood that fouling was the cause. Only having eliminated these would we turn our attention to the engine.
Basically, then, if we believe we have a problem, we need an orderly approach to curing it.
• What is normal?
• What has changed?
• Look at all the symptoms.
• What likely cause(s) matches as many of the symptoms as possible?
• List these possible causes in the order of least cost or, most likely, ease of checking.
• Take some specialist advice if necessary.
• Decide on a plan of action.
• Tackle the job.
But, whatever maintenance you have to do, enjoy your boating!
ENGINES: Cooling system
The majority of the energy contained in the fuel is wasted. At least 25% of this waste goes into the engine cooling system and must be removed, otherwise the engine will overheat and serious engine damage will occur. Any failure within the cooling system may cause a very rapid rise in engine temperature, requiring the engine to be shut down.
Often the first indication of overheating is the overheat alarm. If a temperature gauge is fitted this will give earlier warning, but it’s often overlooked. If overheating is caused by failure of the seawater pump, or blockage of its supply, cooling water will fail to flow from the exhaust, causing a change in the exhaust note. The earlier this is detected, the greater the chance of avoiding failure of the seawater cooling pump impeller.
There are two forms of water cooling:
• Direct (raw water) cooling
The engine is cooled by the water in which the boat floats. So, if you are on the sea, seawater circulates through the engine’s cooling system.
• Indirect cooling
Fresh water circulates around the engine’s cooling system and is cooled by a heat exchanger. Usually seawater (or river water) flows through the heat exchanger to remove the heat. On some boats a keel cooler, mounted outside the hull and immersed in the sea or river water, carries the heat away (see diagrams below).
Direct cooling
This is the simplest system – but with seawater flowing through the engine the waterways will suffer from corrosion. Many older engines are made from cast iron and have thick walls and so have a long life expectancy. Some modern light-weight engines also have direct cooling and may have sacrificial anodes to help control corrosion. It’s essential that you check the engine handbook to find out where they are and change them annually at least.
The thermostat controls how much seawater flows through the engine to control its running temperature. When the engine is cold, no water passes through the engine but flows directly into the exhaust. As the engine heats up some cooling water is directed through the engine’s waterways and then recombines with the main flow before being injected into the exhaust system. If the engine starts to run too hot, all the cooling water flows through the cooling ways.
1 Engine overheating due to blockage
WHY IT NEEDS TO BE DONE
Engine overheating can cause severe damage to the engine.
WHEN IT SHOULD BE DONE
If there is an indication of overheating. Overheating may be indicated by an over- temperature alarm or a higher than normal reading on the temperature gauge, if fitted.
TOOLS NEEDED
Spanners and screwdrivers.
WHERE TO FIND IT
Anywhere, from cooling water intake to exhaust.
HOW TO DO IT
Unless the cause is obvious, you need to work your way around the system, starting at the most likely or the easiest to achieve.
(Knowledge of how a cooling system works is invaluable for troubleshooting.)
How do I know it’s a blockage?
1 If you suspect a blockage, stop the engine.
2 Wait a minute and restart. (With luck this will allow any plastic sheeting or bag, which has been sucked up against the seawater intake, to float clear).
3 Observe the exhaust or listen to it to check if there’s a flow of cooling water.
4 If not, stop the engine again and investigate further.
5 Check the seawater strainer to see if the filter is blocked. Clean it if necessary (photo A). Some builders don’t fit a seawater strainer when installing a Volvo saildrive. If yours hasn’t got one, fit one in an accessible place.
6 A blockage between the seacock and the strainer can often be cleared by means of a dinghy inflation pump or a gas foghorn (photo B). You’ll probably have to disconnect the hose from the inlet to the strainer so you can blow down the pipe.
7 If the strainer is below the waterline, you’ll need to close the seacock first and then reopen it as you blow (photo C).
8 On saildrive engines, the seacock will be found close to the gearbox, (port side on Volvo Pentas and starboard on Yanmars). Early Volvos have a plastic wheel (photo D), which turns through only 90 degrees and is very stiff. Later engines have a lever-operated seacock instead. Yanmars have a brass screw-type cock with a ‘T’ bar handle that needs several turns to close it off. On shaft-drive engines you will have to follow the inlet hose until you find the seacock.
Indirect cooling
All the seawater flows through the heat exchanger all the time. None flows through the engine itself
A circulation pump circulates the fresh water round the engine’s waterways. The thermostat controls how much of the fresh water flows through the fresh water part of the heat exchanger to maintain the engine at the desired temperature.
No anodes are required in the fresh water part of the system, BUT there are often anodes in the heat exchanger itself. Where several heat exchangers are used, for cooling the oil, gearbox or turbocharged air, there MAY be an anode in each heat exchanger.
Seawater strainer
It’s desirable to fit a strainer in the seawater system prior to the seawater pump. This will prevent weed and other marine life from entering the engine’s cooling system. It will also help prevent silt entering the system. Many older boats didn’t have one fitted and, even now, some boat builders don’t bother to fit one either. If you haven’t got one, fit one.
2 Seawater pump
Where’s the seawater pump?
1 On many smaller engines the seawater pump is located on the front of the engine, where generally it’s accessible (photo E1). However, that's not always the case.
2 Older Volvo Pentas have them above the gearbox (photo E2).
3 Follow the pipe from the seawater strainer and you’ll come to the pump.
TIP
Yanmar 2GM and 3GM engines
On the Yanmar 2GM and 3GM the seawater pump, although on the front, faces backwards alongside the front starboard engine mounting. The easiest way to get at the impeller is to remove the pump first (photos F1 & F2). This isn’t as bad as it sounds because only two bolts need to be removed and there’s no need to disconnect the pipes.
Causes of pump failure
• If the pump runs dry it will overheat and the blades will disintegrate. This is the most common cause of failure (photo A).
• Pieces of blade can lodge in the waterways causing a partial blockage and will then cause further overheating. In seawater-cooled engines (direct cooling) the debris could end up almost anywhere and may or may not cause a further problem. Back-flushing the cooling system may cause the debris to return to the pump body, so if you are concerned you may well have to consult an engineer.
• With fresh water-cooled engines (indirect cooling) debris will go directly to the heat exchanger and either lodge there or pass right through into the exhaust (diagram B). Cleaning the heat exchanger tubes is a comparatively simple task.
• Pump impellers sometimes become unbonded from their central metal boss (photo C). The impeller then remains stationary in the pump while the boss drives round. When you remove the faceplate this is not at all obvious, so when you extract the impeller try turning the impeller while you firmly grip the boss to check the bonding. Several batches of impeller suffered from this problem so this can occur very quickly, even with a new one.
• Wear of the pump cam (photo D) will cause a reduced rate of flow. This reduced flow may be insufficient to cool the engine and overheating can then occur.
• An even rarer problem is for the screw holding the wedge-shaped cam inside the pump case to shear. This cam then rotates with the impeller rather than staying stationary so check that the cam is between the inlet and the outlet the ‘short way round’ (photos E and F). If the screw has sheared you’ll probably have to remove the pump to replace the screw. The replacement must not be so long as to stand proud of the cam or the impeller will be damaged. The pump often needs to be removed to access the screw (photo G).
• If there is significant wear on the front plate (photo H), as a temporary measure it can be reversed so that the front side faces the impeller (photo I). Any inscription will not affect the pump’s performance.
Changing the impeller
WHY IT NEEDS TO BE DONE
Failure of the impeller will cause overheating of the engine.
WHEN IT SHOULD BE DONE
The impeller needs to be changed annually as a precaution against failure. Blockage of the cooling water intake will cause the impeller to overheat and fail.
TOOLS NEEDED
Spanners and screwdrivers.
WHERE TO FIND IT
Often on the front of the engine, but it can be on the side or rear.
Changing the impeller
1 Turn off the seawater cock (photo J).
2 Remove the pump faceplate securing screws (diag. K).
3 Remove the faceplate (diag. L).
4 Remove the impeller using longnosed pliers, slip pliers or an impeller removal tool (Jabsco) (diag. M).
5 Inspect the old impeller for wear and cracks (photo N).
6 Insert the new impeller (photo O).
7 Impeller revolves ‘long way round’ from inlet to outlet (diag. P).
8 Replace faceplate and gasket (renew the gasket if necessary).
9 Insert all screws and tighten by hand.
10 Tighten all screws (diag. Q).
11 Re-open the seawater cock (photo R).
When you restart the engine, check the exhaust to make sure that cooling water is coming out, then check the pump faceplate joint for leakage. If the faceplate is hot to the touch, it’s running dry. Make sure that you don’t get caught up in any moving parts of the engine or shaft.
One yachtsman had a cooling water failure and on removing the faceplate and impeller a small eel dropped out into the bilge. You never know what you might find!
TIP
Inserting the new impeller
The new impeller may be inserted either face in, but the blades should be deflected in the correct rotational direction as you insert it. If you bend the blades into place by tightening a cable tie, piece of string or a strong rubber band round the impeller, you’ll find the job of inserting it much easier (photo S).
TIP
Fit a SPEED SEAL
The ‘SPEED SEAL’ by True Marine (photo T) replaces the standard faceplate and gasket with a heavy duty plate and an ‘O’ ring seal. These are attached by large knurled screws, two of which remain captive in the pump body, which need only be finger tight. The advantages are that you are less likely to drop small parts into the bilge and you don’t need any tools to remove the faceplate. Speed Seals are available for most small engines.
Seawater pumps on Sabb engines
Sabb engines have a very different type of pump, employing a diaphragm (photos B1 and B2). This is much more complicated but can be run ‘dry’ for considerable periods without failure. They compare well with impeller pumps, which will run for a maximum of 10 minutes without water to lubricate them.
Seawater pump leaking
WHY IT NEEDS TO BE DONE
The water and oil seals on the water pump shaft will wear with time, leading to pump shaft corrosion or loss of engine oil.
WHEN IT SHOULD BE DONE
A daily check of the pump’s ‘tell-tale’ hole will give advance warning of seal failure.
TOOLS NEEDED
None.
WHERE TO FIND IT
The water pump is often mounted on the front of the engine. However on some it’s mounted on the rear or the side, so check your handbook.
Leaks from the pump body
1 There’s a water seal on the drive shaft and possibly an oil seal as well. The water seal, especially, will start to leak after a while and if this isn’t replaced fairly quickly, shaft damage will occur. If there’s an oil seal it will usually be identical to the water seal, but fitted facing in the opposite direction.
2 The pump body will have a ‘tell-tale’ drip hole on its underside (photos A and B) and any leakage past the seals will be detected here. A daily wipe of the underside of the pump body with a finger will quickly detect the first signs of a leak. You can continue to use the engine but the sooner you do something about it the cheaper the repair will be.
3 Replacement of the seals is beyond the scope of this book but many pumps have a repair kit available. You may need to enlist the help of your dealer to remove and replace the shaft bearings to allow the seals to be changed.
TIP