Author: abmarineservice

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Breakdown on the water

pech-op-het-water

Failures in your engine, collision with a sandbank, a fuel leak… these and other issues cause major problems while sailing and are the nightmare for many a skipper. You can prepare as well as you can, but it is obviously difficult to arm yourself against the unexpected. Do you have quite a bit of technical knowledge and also the necessary tools with you? Heartwarming! But that does not mean you can actually face all issues.

Prevention is hard, cure is not! That’s why you would be very wise to join our partner Vaarzeker to take out a subscription, which ensures you always get the best assistance!

Even if you are not a member, these counsellors may be able to support you. They are just a phone call away from you! Call +31 85 3038253 if you could use some assistance right now. Please note that if you are not a member, you cannot take advantage of free help and there is a good chance you will have to wait longer. Members of Vaarzeker always have priority!

Safety above all

A breakdown is very annoying, but potentially even dangerous! Before calling in Vaarzeker or any other assistance service, it is vital that you are safe yourself first. Especially in case of a fire, leak or power failure. As long as your fellow sailors and you are not at risk, you can plug a leak, put out a fire or switch off the power. In doing so, never expose yourself or others to unnecessary danger, ensure your safety above everything else and call in experts whenever possible!

Subscriptions

As is the case with many services, you are also in a position to decide how much you pay and thus what exactly your options are. That is, you only get assistance with the most important and common problems when you choose the cheapest subscription. With standard or even complete assistance, that package is of course increasingly magnified so that you are carefree on the water! On top of that, the latter two subscriptions offer a 10% discount to boaters who choose to pay per year instead of per month. The three modules are:

Breakdown Assistance
This module includes:

  • Call-out charges
  • On-board assistance
  • Starting aid for battery problems
  • Throughout the Netherlands except home port

As long as you are ashore, you can count on the most comprehensive assistance from experienced mechanics thanks to Breakdown Assistance. They do their utmost to get you out on the water the same day. Do you also want technical support while on open water? Then read on quickly!

Assistance Standard
If a technical failure occurs while you are on small inland waterways, your vessel will be towed to a safe port. The Wadden Islands are excluded.

This module includes:

  • Call-out
  • Towing off
  • Telephone assistance for technical questions
  • Telephone nautical advice

For a small extra fee, the Breakdown Assistance module is included in this. It is then offered at a 10% discount. Moreover, Assistance Standard is offered throughout the Netherlands, including your home port.

Assistance Complete
Whatever water you find yourself on, you will benefit from a comprehensive assistance package

This module includes:

  • Call-out
  • Towing off
  • Telephone assistance for technical questions
  • Telephone nautical advice
  • Floating after jamming
  • Supply of spare parts
  • Fuel delivery
  • Towing from port to port
  • Removal of objects from propeller

As with Assistance Standard, you can add Breakdown Assistance to this package: in this case, you get a discount of up to 15% on it! Assistance Complete can be used throughout the Netherlands, including your home port.

Carefree boating

When you go out on the water for fun, you always want to be able to count on experts to help you. Got a problem on board? Then you know who you can count on! After making just one phone call, Vaarzeker’s professionals will come to you to solve your problem. Depending on the situation, you can simply sail on to your final destination the same day. Give yourself that peace of mind, become a member and sail for sure.

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Water-lubricated propeller shaft leaks

boatymacboatface

To function, your ship’s propeller shaft runs from inside to outside, through the hull. Of course, this component is built and installed so that your vessel does not fill up with water, but still, your water-lubricated propeller shaft may leak. Naturally, this is a dangerous situation that you want to prevent or remedy as soon as possible. But how does this arise and how do you fix such a problem? Read on to find out why your water-lubricated propeller shaft is leaking and what to do about it.

Water-lubricated propeller shaft leaks: the cause

There is a difference between a grease-lubricated and a water-lubricated propeller shaft seal. Variants from the first category are easy and low-cost to maintain, but grease replacement is difficult. Moreover, some of this ends up in surface water, which is not environmentally friendly.

A grease-lubricated propeller shaft seal is easily converted to a water-lubricated one. You don’t have to constantly lubricate the grease pot and it is much less polluting anyway. But sand grains are capable of causing considerable wear to the sealing rings. And that, in turn, is the basis for a leak!

Furthermore, your engine may be set up a little too flexibly, meaning the packing rings are not sufficiently able to follow the propeller shaft movements. In addition, a leak may be due to stuffing boxes that seal radially and do not adjust to propeller shaft misalignment. Finally, it is possible that the axle itself may wear out and thus let in water.

Water-lubricated propeller shaft leaks: the solution

The bearings of a water-lubricated propeller shaft installation are made of rubber. These may need to be replaced once in a while to prevent or fix leaks, if you already suffer from leaks.

Do you often sail in waters known to be shallow or sandy for other reasons? Then it’s better to switch to a grease-lubricated propeller shaft. Indeed, as we explained above, that sand is going to affect your seal much faster than you would like. You are much less likely to suffer from that with a grease-lubricated system. The downside is that this requires much more maintenance. That is much less the case with a water-lubricated propeller shaft. But periodically checking that all components are still in full working order can never hurt.

Questions?

That comes in handy, because we have answers! Now if you have a problem with your water-lubricated propeller shaft that is not mentioned here, feel free to contact us . Explain the problem to us so that we can provide you with a suitable solution. Besides just a method, we also have the best parts for you, such as a complete propeller shaft seal, a coupling and a grease cord.. You can easily install these yourself. At AB Marine Service, you can only assume the very highest quality, because we do offer it!

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How to connect a boat alternator

Does the indicator light on your dashboard stay on or does the battery not have the energy to start the engine after a while? Then is it time to replace the alternator of the boat engine.

Follow these 3 steps to replace an alternator yourself

  1. Disassembling the alternator
  2. Buying the right alternator
  3. Installing the new alternator

Or go straight to:

With conventional dynamos and alternators, one thick cable runs directly from the plus pole of the battery (Terminal B+) or to the distribution point at the starter motor.

After switching on the alternator, a control light on the dashboard indicates whether the circuit is complete. As soon as you turn on the ignition, it starts to light up until the alternator provides counter voltage while it is running. Is there no signal? Then also check the supply up to the contact L or D+ on the alternator.. You can also simply connect it to mass and see if it lights up.

There are also ‘mass-free’ alternators. This means that the whole installation is free from mass (often the engine block). In this case, these cables must also be disconnected.

Often, the alternator’s AC signal is used to drive the rev counter. This is often indicated on the alternator as W-connection. If your rev counter does not work either, this is another indication that something is wrong.

Dismantling the alternator


Switch off the electrical system and disconnect the battery or mass switch. Check that there is indeed no voltage on the cables and that the charging cable runs to the battery (B+) or distribution point. Disconnect the alternator’s electrical wires. Mark the disconnected wires so that you know where to put them again later. Now the alternator is free from the electrical system. Now take it from the engine. In general, it is attached to the front of the engine by means of a clamping and mounting bracket. Accessibility is not always ideal, especially not in a tight engine space, so it may require some creative socket wrench and extension work. Loosen the belt by releasing the tensioning device (1 & 2). Remove the suspension bolt (3).

Dynamo vrij maken van motor

Buying the right alternator for your boat

On our website you can easily search for the right alternator. The easiest way to find the required alternator is by its number. The number is often printed on a label or engraved on the housing.

You can also search under the category Alternators for the make and type of the marine engine or search by engine type in the search bar. The dimensions and specifications of each starter are shown. The most important measures are in any case dimensions J1 and J2 (in the drawings C and A) and of course the entire suspension design.

At AB Marine service you can buy a (replacement) alternator from:

  • Bosch
  • Delco Remy
  • Denso
  • Duccelier
  • Femsa
  • Hitachi
  • Iskra
  • Lucas
  • Magneti Marelli
  • Magneton
  • Melroe
  • Mitsubishi Motorolla
  • Paris Rhone
  • SEV
  • Valeo
  • Visteon
  • OEM

See also our video: How to find the right alternator for your boat.


Installing the new alternator

The installation of the new alternator is carried out in reverse order to the steps described above. Make sure that all surfaces are corrosion-free and clean. N.B.: Grease is not conductive. You should therefore always grease the material after installation. This acts a protective layer against moisture penetration. For proper protection between the contacts, use contact spray or conductive paste.

Alternators: Codes and facts

Connecting an alternator is not complicated if you know what the codes mean. In all cases, we are talking here about alternating current dynamos.

Code L or D+: Light on dashboard

In most cases, a ship or boat alternator functions quite simply. A light in the dashboard comes on when you turn the ignition key. If the engine is running, this light will be off again. When the alternator is malfunctioning, you can sometimes see the light burn weakly. This means that the dynamo has low capacity and does not provide sufficient counter-voltage, so that current slowly flows and the light stays on (weakly). If the light does not work, the alternator does not start either. This contact is often referred to as L (Light) or D+ (Dynamo+)

Code IG or R: Always voltage for the alternator

The IG or R contact is a switched wire from the ignition switch. The wire supplies voltage directly to the alternator regulator so that it always receives voltage to switch on.

Eenvoudige L en IG aansluiting met T-stekker

Simple L and IG connection with T-connector

Code B+, A or 30: Output voltage

An output voltage and current goes from the alternator to the battery. Sometimes there is a diode separator in between to allow two battery packs to be charged separately. You then divide the flow, as it were, into two parts. We usually recommend the use of a battery splitter relay, as it will take less voltage from the charging voltage.

This outgoing voltage wire is often thicker than the other ones and is generally red. It is designated as B+, A or 30.

Minus sign and code G: Mass point

Anything with a minus sign or G for Ground indicates a mass point and can be connected to the motor or minus cable.

Code W: Tachometer or rev counter boat

Then there is the tachometer or rev counter. The alternator generates an alternating current. Each of the coils (usually 3) receives a Hertz signal that is proportional to the number of revolutions. The tachometer converts this signal into an indicated value.

Alternators: Connection codes per brand

All connection codes per brand are indicated in the picture below. American dynamo models often have a completely different coding than the Japanese and German variants. But basically, you will often find the most important and common codes B+ (battery), D+ (light) and W (rev counter).



More information about the electrical circuit and circuit testing the installation?

While sailing, the battery is charged by the alternator on the engine of your vessel. A battery supplies 12 or 24V. If you want more on-board power, choose a larger alternator that delivers more current. In most cases we can supply an alternator with the same dimensions. Get into contact, please send us the current set-up and as much information as possible. Then we will find the right customised alternator for you.

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How to replace the fuel filter of my diesel engine?

This is how you replace the fuel filter of a diesel engine:

  1. In case of contamination, when there is a drain valve, drain the bottom layer of diesel from your tank. Otherwise, pump up a few litres of diesel from the bottom of the tank. In that case, use a pump with a hose (in the filler cap) that reaches the bottom.
  2. Is the (pumped up) diesel full of sludge (diesel bacteria) or water? Pump or tap the lower part completely out of your tank. Repeat this procedure until no more water or sludge can be found.
  3. Is the diesel clear? And not dark or cloudy? Then the job is done. Then there is no need to replace the fuel filter.TIP: Add an anti-bacterial agent to the diesel to kill the last bacteria and prevent them from multiplying again. The De-Bug magnetic filter prevents diesel bacteria.
    If the diesel still looks abnormal, empty the entire diesel tank by pumping or draining. Then clean the tank.
  4. Do you see water or sludge? Then replace your fuel filter. Tip: Is there often water in your diesel? Check the venting of your tank. Sometimes the air vent is located in the hull in such a way that rainwater runs into it or large waves push water into it. Then use a tank dryer in your tank. A simple and effective solution against condensation.
  5. Change the coarse and the fine filter of your system every autumn. Are you installing a tank dryer? Also replace it annually.
  6. The fuel lines are often clicked onto the filter with a kind of clamp, which can easily
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When should I change the fuel filter of my diesel engine?

When there is water, diesel bacteria (sludge) or dirt (under) in or on the fuel tank, it is time to replace the boat’s engine fuel filter.

Therefore, check the filters of the fuel system regularly. E.g. annually when preparing the boat for winter. Do you see water or dirt in the inspection hole of the filter? Then it is likely that there is also water, diesel bacteria (sludge) or dirt at the bottom of the fuel tank. In that case, replace the diesel fuel filter.

Also read: Slime strings and clogged fuel filters

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How to test and replace glow plugs in the diesel engine of my ship or boat

What are glow plugs?

A marine diesel engine has electric glow plugs that help it start when cold. Diesel engines use spontaneous combustion by compressing oxygen and fuel. Just before the highest pressure is reached and the piston is in the top position, fuel is injected through a vaporiser and the combustion process begins. As the engine can be very cold after not running for a while, it may need a little help. That is where the glow plugs come in. Glow plugs are located in the combustion chamber of the engine and are made of high-grade materials.

Testing a glow plug

To test the glow plug, measure the resistance using a multifunction meter or ohmmeter The wires are to be disconnected before measuring. The exact value of each plug varies, but a defective plug can easily be distinguished from a working one. If a current passes through and the ohmmeter shows a value, it would be fair to assume that the plug is in working order. If it reads infinite, there is an interruption and it would be fair to assume that the plug is defective.

Two types of glow plugs

Glow plugs come in two different types:

  1. Parallel glow plugs

    Parallel glow plugs are connected to earth (engine block) via the entry. The current flows back to the battery via the screw thread. They have one entry and are connected to one another. These are usually the Quick Glow Systems that run on the direct battery voltage.

  2. Serial glow plugs

    Serial glow plugs are working like a light bulb. These are often seen in old systems or spiral filaments. They have an incoming and outgoing wire or connection to the next one. The first plug is the entry and the last one is connected to earth. They work on reduced voltage with pre-heating resistors and a glow eye.

DIY replacement of glow plugs on a marine engine.

Remove any defective glow plugs. NB: they can be very tight, so be very careful, especially when dealing with thin-walled glow plugs. Spray generously with penetrating oil before removal if corrosion has built up around the plugs. Thicker plugs are less particular because of their different diameter and plug ratio.
Keep the area around the opening of the motor clean. Watch the maximum loosening torques (Nm = Newton metre = unit of torque) and the thread size (M).

Tip: also use a torque spanner for loosening.

Maximum loosening torques

  • M8 – 20 Nm
  • M9 – 22 Nm
  • M10 – 35 Nm
  • M12 – 45 Nm

Fitting new glow plugs

When fitting new glow plugs, it would be best to use the tightening moment as prescribed by the engine manufacturer. A little copper grease on the cutting edge and the thread is recommended. Tightening is also done with a tightening moment. They only need to seal. Indication of tightening moments for electrical connections:

  • M8 – 10 Nm
  • M9 – 12 Nm
  • M10 – 15 Nm
  • M12 – 22 Nm

Tightening moment for electrical connections

  • M4 – 2 Nm
  • M5 – 3 Nm

Removal of jammed glow plugs

When the maximum removal torque has been reached, discontinue the loosening effort and do not overstrain. That is because the glow plug may break. And that means dismantling the entire cylinder head. Try to loosen the glow plugs in the following three steps:

  1. Loosening: Spray with penetrating or synthetic oil. Repeat several times during the day and leave it to soak in overnight.
  2. Heat the plug: Expanding and contracting materials may create more play. Tune up the engine or use a power cable to warm up the self-regulating glow plugs and proceed a little longer than usual. Repeat this procedure. Please note: This procedure works only on glow plugs with 11 – 12V operating voltage.
  3. Loosening: Try to unscrew the glow plug once again. Using a suitable tool, carefully unscrew the glow plug in the cylinder head. A long, extended socket wrench often works better than a spanner. This will distribute the force more evenly without the need for straining it sideways. Use a tap wrench to work with both hands. If no luck, repeat the above three steps.
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How to install an inboard engine?

Are you going to install or re-install an inboard engine yourself? Then prepare yourself well, start with the basics and start measuring. Then you can replace an engine with minimal adjustments. For recent engine types, you often know the installation dimensions or they are easy to find. Pay particular attention to:

In any case, consider what you will need.

Propeller shaft height

First check if the engine matches the propeller shaft height. Are the reverse clutch output and the crankshaft at the same height? If the reverse clutch output is lower than the existing propeller shaft, the engine will ‘rise’.

Engine mounts

On some inboard engines, adjusting the existing engine mounts is not a problem. In case of a steel ship its foundation can be adjusted. In a polyester ship, this is more difficult. Therefore, please check in advance what is possible. Especially with a saildrive, you are often bound to prefabricated through-hulls.

Maximum tilt

Also check whether the inboard engine can handle the maximum tilt when sailing. The maximum tilt can often be found in the manual. A homokinetic drive solves the problem in a different way.

Reverse gear

The Velvet, PRM, Hurth, ZF and Twindisc reverse gears are well known common types. The ratio is often given as engine speed divided by the output speed, e.g. in the ratio of two to one (2:1). This ratio means: Two engine revs / one propeller shaft rev (or simply half).

Often the direction of rotation is indicated with L or R. L 2:1 therefore means: a two-to-one left-hand reverse gear for a left-handed propeller.

You may also come across gears, e.g. for Volvo Penta, with an A for Angle. The axis of these reverse gears is rotated by 7 degrees. Then the motor does not have to tilt as much.

Propeller

Note the direction of rotation of the screw. There are left-hand and right-hand reverse gears. The direction of rotation of the gearbox is determined with the ship moving forward and you looking at the bow.

Be careful with a ‘Z-drive’. The engine will then be reversed, so check the specifications carefully.

AB marine service can carry out the power requirements calculation for your ship.

Power

If you keep the power in the same direction, you can often use the same supply and return connections, such as the exhaust gas outlet, cold water inlet or circulation pipes.

If you are going for larger or smaller power, check the diameter of the connection on the engine. This is already a good indication of the required size.

If the exhaust manifold has a 45 mm diameter, you can use that one. Do not use smaller diameters, this will cause the engine to brake, with all its consequences. Bigger ones are often not a problem.

Propeller shaft and bearing

Also think about connecting the propeller to the reverse gear. Some brands are interchangeable, but this is not always the case. In that case you will need an adapter flange. These are available separately on request or are supplied ready to use with a homokinetic drive.

Want to prevent vibration and save time when connecting? Consider the advantages of a thrust bearing with a homokinetic drive.

What do I need?

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I have a 12V battery, but the alternator says 14V. What is the difference?

In boats, you have got 6V systems (old, but still common), 12V and 24V systems. The 12V is most common in pleasure cruising and 24V is found in larger ships and inland vessels.

This voltage is energised by the battery, which is recharged by an alternator on the combustion engine. This voltage is higher in order to fill ‘the vessel’ quickly. Without a voltage difference there is no ‘flow’. This creates the confusion between the terms system voltage and charging voltage.

There are also different batteries: starter, traction and semi-traction, sometimes with their own charging value. Real full-traction batteries require a higher charging voltage, always check this when purchasing.

On the AB Marine service site, we use the term ‘system voltage’ as much as possible. A 12V battery must be charged with a 12V alternator. Therefore we use the indication 12V for the alternator. Using the 14V or 13.8V charging voltage as indication would lead to confusion. We supply the alternators standard with a set value for charging starter and semi-traction batteries.

  • 6V calcium battery = 6.9V charging voltage (e.g. vintage car)
  • 12V calcium battery = 13.8V – 14.4V charge voltage (all starter batteries and common semi-traction batteries).
  • AGM semi-traction battery = 14.6V – 14.8V charging voltage
  • GEL battery = 14.2V – 14.8V charging voltage

It is also possible to determine the status of your battery by measuring the voltage, see the corresponding voltages below. Preferably do this a day after charging.

Gebruiksaanw. / Handleiding - Accu Service Holland

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Is your expansion vessel or cooling system running empty?

Is the expansion vessel or cooling system (slowly) losing pressure? It could be a leak in either direction.

First make sure that there is no leak to the outside of the engine. Leaking cooling liquid can evaporate quickly when the engine is hot, which makes it hard to detect. Look for traces of dried cooling liquid. This has usually the colour of the liquid itself: yellow, green or red, depending on the brand and type of liquid. It can easily be fixed by tightening the hose clamp or replacing a cooling water hose.

Sometimes, the leak may show up when using a pressure tester to apply pressure on the system. Also check that the rubber seal of the radiator cap (or expansion cap) is still intact and not worn out.

What if no traces of leaking cooling liquid can be seen?

If the liquid does not run out, it may also escape via the heat exchanger that is connected to the water from outside the vessel. It means that – the other way round – water from outside the vessel enters the cooling system.

As a test, pinch off the outgoing cooling hose from the water from outside the vessel at the exhaust injection elbow. With the engine running, the impeller pump should be building up pressure (no risk of damage) and the cooling system should start filling in case of a leak between the outside water system and the engine heat exchanger. The fluid level in the expansion vessel should rise. That is when it is time to replace the rubber sleeves. The sleeves separate the ”outside water system” from the ”coolant system”.

If all the above is not the case and the motor oil contains no cooling liquid, the engine may also have let cooling liquid enter into the combustion chamber. The cause could be a leaking head gasket or cracks in the cylinder head. Many mechanics cannot determine this fault from the outside for sure. Especially in case of a small leak, this is very unpleasant and hard to assess.

Possible solutions include:

A simple pressure tester (also useful for the first and second step). A low-cost solution, but make sure that the kit comes with the right cap. The tester is also available from AB Marine service, if so required. Alternatively, a nitrogen tester is also a reliable testing tool. It shows when nitrogen from the combustion gets into the cooling liquid. For this, google on e.g. “cylinder head leakage tester kit”.

If you cannot find the cause in steps one and two, remove the cylinder head for further inspection.

Spare parts for the cooling system

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Starting problems? 3 tips to fix.

Here are some tips in the event that you have a battery-related problem or a malfunction in the starting system.

If the engine of your boat has little or no power to start, the starter motor or battery may be defective.First things first: make sure that you have checked the following before you start looking at replacing these parts. Several other things, such as a corroded main fuse, mass switch or soiled electrical connections and poorly connected wiring, may be the cause of a starting problem.

Make sure you are safe before you start working.The engine should only run through the starter motor without starting, so turn off the fuel supply. This can easily be done by using the stop solenoid or by putting the throttle in the stop position. Let’s get the multimeter out and do some testing!

1. Battery check in a few steps!

Step 1: A full battery; set the multimeter to DC (direct current) voltage, connect the red probe to the positive and then the black probe to the negative battery terminal. If the multimeter indicates that the battery output is less than 12 volts, first charge or replace the battery before we continue. At 12.4 volts, the battery is fully charged. Double that figure (24.8 volts) for a 24-volt battery. A few millivolts more or less is okay.

Step 2: Put the multimeter back on Direct Current. Connect the red wire of the multimeter to the positive terminal of the battery, and then the black wire to the negative terminal. Proceed with step 3.

Step 3: Turn the ignition lock to the “Start” position and start the engine, keep it going for about 4 to 5 seconds.Read the voltage as shown on the battery multimeter while starting the engine.The battery is in order if the multimeter reading exceeds 9.5 volts during start-up. A reading of less than 9.5 volts indicates too high a drop in voltage. The cause may lie in a poor chemistry transfer in the battery itself due to age. About time to replace it! Battery in order? Keep on reading.

2. Weak starter.

Since the battery has found to be in order or replaced, it is now time to have a look at the starter motor. Even though the battery was the only problem, the following test may prevent many headaches in the future. Corrosion is a common problem. Check the connections from the battery to the starter itself for any deposits, including the negative terminal. Also check the condition of the connection between the starter and the engine block. This includes disassembly and inspection, but taking measurements could be a faster option in this case. This can be done as follows:

Step 1: Put the multimeter on Direct Current. Connect the red probe to the positive battery terminal and then on the relay connection of the starter, from where the copper cable enters the starter motor. This is the last connection before the + plus disappears in the starter motor itself. Below called the “M terminal”.

Step 2: Turn the ignition lock to the “Start” position and start the engine without running it. Read the voltage as shown on the multimeter while starting.

Step 3: Without drop in voltage between the cable and the starter relay, you should now read 0 volt. But people often read 0.1 volt, and 0.1 to 0.2 volt is no exception for older systems.

It means a voltage of e.g. 12.1 volts starts from the battery, but – due to resistance or a poor contact – ends up at only 12.0 volts. A multimeter measures the voltage difference.So the multimeter will measure a “difference” of 0.1 volt, any number higher than 0 volt indicates resistance. This process can be repeated on the plus terminal for each individual contact and connection, as well as for the negative terminal. That is because every positive electrically charged atom that goes in has to come out again via the negative terminal.

 

Starter meter

Step 4: Add up the values of the measurements in the previous steps. The sum of these values should not exceed 0 to 0.3 volt. The lower the number, the better it is. Just think of it. When starting an ordinary 4-cylinder boat engine, it will run up to 1000 Amps for a short period of time from standstill, after which it will drop until the engine runs at about 200 to 300 Amps. Until the engine runs 1000 Amps with 0.3 drop in voltage, the starter motor will drop 300 Watts. For a standard nominal 1200-Watt starter motor, it means that 25% of the starter capacity is lost. It shows that a minor drop may have major consequences. (example)

3. Conlusion.

First fix the resistance loss and then check that the power of your starter motor is back.
This was about testing the power supply of your starter system. If the starter motor still fails to give full power, it may have an internal defect. In that case, we suggest that you contact one of our specialists for more information about a possible solution.

 

Facts!

R = U / I or Resistance = Voltage / Current or Ohm = Volt / Ampere (Ohm’s law)

P = I * U or Power = Current * Voltage or Watt = Ampere * Volt

Watt = Ampere22 * Ohm
Watt = Volt / Ohm
Ampere = Watt / Volt
Volt = Watt / Ampere

An example with water flowing through a tube gives a better insight into the difference between current and voltage:

Electric charge in volts:pressure of the water in a tube.
Current intensity in Amperes:amount of water per second flowing through a tube.
Resistance in Ohm: thickness of the water tube.
Power in Watt:force of the water against e.g. a paddle wheel.

Click here to read more about replacing the starter motor

Replacing a starter motor yourself? In 3 steps.