Water motorists themselves select the engine for their boat, boat or yacht.
A tachometer, a device for measuring revolutions per unit of time, will help you break in, load the engine correctly, and select a propeller with the required characteristics.
In a boat motor, it reads the electrical impulses generated by the generator and measures how fast the crankshaft rotates. If it is not possible to connect the tachometer to the alternator, a tachometer sensor is required. Some models remove impulses through the insulation from the spark plug wire.
The device displays the result in numbers on an electronic display or arrows on a dial.
He hears the difference in speed
Tachometers for PLM help solve fundamental problems:
- Control and adjustment of engine operation
- Determining the maximum number of revolutions that the motor develops
- Selection of the optimal operating mode of the PLM
- Troubleshooting
This will help you choose the right one. Using a boat tachometer reduces the rate at which engine life decreases due to incorrect settings. Saves fuel. In short, it protects the engine and allows you to achieve an optimal balance of speed and efficiency of the craft.
A useful function of some models is the calculation of engine hours, the total number of hours of operation of the outboard motor. This figure is comparable to car mileage figures.
Which tachometer to buy
When choosing, the following criteria are taken into account:
- Compliance with the technical parameters of a specific PLM. Manufacturers produce universal models and differentiated devices for two-stroke and four-stroke engines.
- Dimensions.
- Easy to install and operate.
- Functionality and availability of advanced features.
- Type: analog or digital - digital is cheaper, analog is more common.
- The device requires a battery.
- Leak tightness: Water may enter “collapsible” tachometers with replaceable batteries.
Installation and configuration
Installing a tachometer for a boat motor is quite simple. Following the instructions, the navigator is able to carry out installation independently. The tachometer is mounted on the tiller or on the dashboard of the boat. The choice depends on personal preference as well as ergonomic considerations. In the second option, the following aspects will have to be taken into account:
- Standard signal wire length.
- Position of the screen (dial) - the steering wheel should not block the view.
The sequence of connecting the terminals to the contacts is indicated in the instructions. And the method of fixing the device is determined by the choice of location for installing the on-board tachometer and the design features of the mortise or overhead housing.
The next mandatory stage, without which the previous ones lose their meaning, is setup. How to do this correctly is indicated in the instructions for the specific model.
Precisely adjusting the tachometer to the outboard motor will allow you to evaluate the performance of the boat without errors, as well as understand whether the “duet” of the propeller and the engine is chosen correctly, without forcing you to painfully listen to its speed.
To help you with the difficult choice of a suitable tachometer, our online store has consultants. They will explain all the nuances, call: +7 800 555-47-89.
With a car or motorcycle engine, we can say with complete confidence that compared to them, the first one is not very complicated. Therefore, manufacturers do not install additional measuring instruments and sensors on it, as this will make the motor itself more expensive. But sometimes, when operating an engine, it is desirable to have information about such parameters as mileage (motor hours) and engine speed. These parameters cannot be determined without the use of additional instruments. This can only be done with the help of special instruments - tachometers.
The tachometer is a small and fairly easy-to-use device. It is designed for installation on outboard motors. It should be noted that its installation is very simple and is carried out without direct intervention in the engine itself. Made from waterproof material. The weight of the device is small, generally no more than sixty to seventy grams.
Operating principle
The device reads the pulses that go from the power wire to the spark plugs. It is important that the pulses are read through the insulating material. The method of induction works here. Thus, you can get engine speed that happen in real time. In addition, you can calculate the time during which the motor worked (motor hours). It should be noted that some devices receive information from Magdino coils. These coils on the motors act as a generator.
There are boat motors on sale that do not have a signal from the generator. In this case need to use tachometer, where its own power supply is installed.
All received data is displayed on a small screen as follows. The revolutions are displayed in real time, and the engine hours are displayed after the engine stops running. Tachometers can count engine hours for a certain period of time, for example, one day, and the indicators can be reset, but the number of engine hours for the entire time cannot be reset.
What is a tachometer for?
This device is necessary to determine the exact number of revolutions in real time during engine break-in. Running in the engine occurs over a certain period of time and must occur at strictly defined speeds. This is all indicated in the passport. If the number of revolutions differs from the nameplate, this will lead to the fact that the outboard motor will work much less.
The fisherman, by counting the time during which he swam, can approximately determine how long it takes to consume a full tank.
If the data on the device differs greatly from the passport data, then this indicates some kind of problem in the motor.
You can determine at what speed the lowest fuel consumption will occur.
It should be noted that the tachometer can help with issues related to changing the speed of the boat. To change the speed of a motorboat, you need to change the speed of the engine shaft. To do this, select a screw with a smaller pitch. Using a tachometer, you can determine the most optimal propeller option for the motor.
Tachometers are of the following types:
- universal. They can be used for any type of engine;
- for two-stroke engines;
- for four-stroke engines.
Tachometers are also divided into analog and digital. In analog tachometers Engine speed is shown on the dial indicator, and in digital – information is displayed on a digital display.
Installing a tachometer
If the device has its own power source, then you do not need to have any additional tools with you for installation. The wire coming out of the device must be wound to the wire that goes to the spark plugs. The cable is wrapped around the wire coming from the candle four or five times, and the distance from the candle should be approximately five centimeters. The coils need to be secured with tape.
After this, you need to secure the device itself. To do this, you can use self-tapping screws. After the device is secured, all that remains is to run the cable from the high voltage wire to the device itself. This cable must be purchased. It contains terminals and connectors protected from moisture.
If there is no own power source, it reads pulses from the magneto coils themselves. This is where the cable needs to be connected.
The market for tachometers for outboard motors is very diverse. You can purchase devices from both very well-known brands and completely unknown manufacturers. In addition, there is a high risk of purchasing a fake. Therefore, when choosing a tachometer, it is advisable to first choose a high-quality and reliable seller. To do this, you can ask friends or acquaintances about this seller. You can look at reviews on the Internet.
When choosing a tachometer, you must pay attention to the following:
- its functionality. The thing is that some devices can only show the operating speed of the engine, they do not show the minimum and maximum;
- on some models it is possible to view engine indicators such as: oil pressure, temperature, and so on;
- You need to take into account that some functions will only work if you have special sensors, which are not always easy to install. Most users believe that the most necessary function is the engine hour counting;
- technical characteristics must correspond to the parameters of the motor;
- ease of installation;
- tightness. Most tachometers are sealed. This means that the power supply can only be replaced by disassembling the case itself. In some devices batteries can be replaced without disassembling the body itself. This is very convenient, but this feature can lead to water getting inside the device;
- compactness;
- price;
- when purchasing, you need to make sure that the device has a sufficient speed of updating information on the screen;
- The screen is bright and clear. This is important especially in sunny weather.
Tachometer setting
When setting up you need check the number of revolutions engine while idling with tachometer readings in the same mode. If the indicators do not match, they must be brought into compliance using the instructions.
If a universal tachometer is used, it is necessary to set the operating mode selector to a position that corresponds to the number of pulses per revolution of the engine crankshaft, provided that it is connected to the magneto. In this case, the type of engine used does not matter. The number of pulses can be viewed in the table included in the manual. Setting the modes must be done with the engine turned off.
Review of the most popular models
Manufacturers of outboard motors generally do not supply tachometers for their motors. This task is carried out by partner companies. For example, a company called Teleflex Marine makes a large number of tachometers and puts the Mercury logo on them. The same company produces Osculati and branded Teleflex tachometers. In addition, many companies from Taiwan and China also produce tachometers with the logos of such well-known manufacturers as Yamaha and Suzuki.
Models from this well-known manufacturer have a body that is well protected from moisture. They are installed in eighty-six millimeter instrument panels. They are successful used with Yamaha motors series from F50 and above. The display shows the maximum and minimum engine speed and shows the number of engine hours.
Mercury.
Manufactures analog tachometers that are installed in Mercury engines. The device is equipped waterproof case with glass, which does not fog up. Pointer dial.
Manufactures analog tachometers. They can be installed in Suzuki DF9-30/DT25-40 engines, in which they are installed in a special crankcase hole with a diameter of eighty-six millimeters. There is no operating mode selector, since all motors have twelve-pole generators.
So, we can conclude that a tachometer for a boat motor is a necessary thing. Thanks to the fact that today You can buy tachometers of a wide variety of characteristics and manufacturers on the market., and also thanks to the simple installation, more and more people are coming to the conclusion that it is necessary to purchase a tachometer.
Motors for boats have a simpler structure than engines for motorcycles and cars, so they are not supplied with measuring instruments. When operating a boat, information about the number of engine revolutions may often be required. The tachometer allows you to obtain this data. It helps in choosing a propeller, adjusting the motor, allows you to determine a more economical mode for starting the engine, and check for possible malfunctions in the operation of the mechanism.
Types of boat tachometers
The crankshaft rotation speed determines the number of pulses entering the electrical system of the motor. Their number is counted by the tachometer. Magdino coils are generators in boat engines, and the tachometer reads information from them.
Induction tachometers for outboard motors are devices with individual power sources. They are intended for engines that do not have generator signals.
The tachometer recalculates the data and displays the number of crankshaft revolutions over a fixed period of time. Pointer-type indicators or liquid crystal displays are used to display information.
According to their purpose, tachometers are classified into the following types:
- universal (can work with engines of various types);
- two-stroke;
- four-stroke.
The data output type divides devices into two categories:
- analog, having an indicator with arrows;
- digital with a digital display.
Digital tachometers can interact with other measuring devices (hour meters).
There are a variety of tachometer models on sale, produced by well-known companies or less popular manufacturers. There is a possibility of purchasing a counterfeit device, so before purchasing it is recommended to look at reviews about the model and consult with friends and acquaintances who have previously purchased similar products.
When choosing, you should consider the following structural features and factors:
- set of functions;
- compatibility of tachometer and boat engine;
- complexity of installation and configuration;
- tightness of the device;
- compact size;
- price.
The device can display only the engine speed or additionally show temperature, number of engine hours, oil pressure and other characteristics. Advanced features require more complex sensor installation.
Typically a device with an engine hour sensor is used. Using this function, a new engine is tested and its service life is determined. It is better to choose a device that records engine hours per trip and their total number since commissioning.
Universal tachometers are equipped with a switch that changes operating modes in accordance with the engine used. Switchless instruments only work with the specific engine types for which they were designed. There are devices compatible with motors from a certain manufacturer.
Most often, the power source is located in a sealed case, which will need to be disassembled to replace the battery. This structure allows you to protect the device from water ingress. Some models have a separate cover for the batteries, which makes them easier to remove, but this breaks the seal.
Device prices are significantly higher for models from well-known manufacturers. Such devices often have a large set of functions that increase their cost. Only some of the available functions may be needed to operate the device, so it is advisable to purchase a cheaper and simpler model if the budget is limited.
The digital model should check two parameters:
- frequency of updating data on the screen;
- clarity and brightness of the numbers displayed on the display.
Most popular models
The most popular models of boat tachometers are represented by the following brands:
- Yamaha;
- Mercury;
- Suzuki.
The Yamaha 6Y8T-8350T-11-BK multifunctional digital tachometer has a sealed housing that reliably protects the device from moisture. It is mounted in a standard 86 mm socket on the dashboard and is compatible with Yamaha motors (F 50 and above). The display shows engine hours, maximum and current engine speed. The cost of this model is 23,600 rubles.
Mercury Flagship analogue tachometer (0−8 thousand rpm) can be installed on any variety of Mercuri engines. The device case is resistant to moisture, equipped with anti-fog glass and an arrow dial. The price of an analog tachometer is 5600 rubles.
The Suzuki analog tachometer is used for DF 9.9 and DT 25−40 engines. Installs in a standard 86 mm socket. The model has fog-resistant glass and a sensor that reads up to 7 thousand engine revolutions. Suzuki engines are equipped with 12-pole alternators, so there is no mode switch on the tachometer. The device costs about 4400 rubles.
Installation of the device
Installing the device is not difficult; almost any user of a boat with a motor can do it. The device is mounted on the instrument panel or on the tiller motor, depending on the type of design.
Installing a tachometer includes the following series of actions:
The connection also has some features, depending on the type of device design:
- For a tachometer without a power source, the cable must be connected to the magneto coils from which the pulses will be read.
- If the device has a power source, the spark plug wire is wrapped in connecting harnesses. The number of turns and the distance to the spark plugs are indicated in the instructions (usually 3-6 turns and a distance of 4 cm are sufficient). The tachometer terminals are connected to the harness.
The cable should not come into contact with moving or hot parts of the motor. Connections are made strictly according to the diagram. When the engine is properly connected and started, the device will begin to count the number of revolutions. You can adjust the displayed data using settings.
Setting up and selecting an action mode
General setup involves selecting the operating mode of the device in accordance with the operation of the motor.
Models working with the same type of motors from different manufacturers or different engines from the same company show a more accurate number of revolutions when starting. By starting the engine in idle mode, you can compare the data with the indicators in the instructions. If the values differ, then it is necessary to configure the device according to the manual.
In the universal model, you need to set the selector to one of the positions:
All work on setting up the device is carried out only with the boat engine turned off.
An optimally selected and correctly installed tachometer will allow you to accurately monitor the operation of the outboard motor and promptly notice its failures and malfunctions.
They have a minimal engine condition monitoring system. Manufacturers do not complicate the outboard motor with measuring sensors. A tachometer is the best way out of a difficult situation. This device will keep you informed of the engine speed and total operating hours.
The tachometer is a small-sized and easy-to-use device that is designed for installation on a motor boat engine.
Installation is carried out without direct intervention in the engine itself. The device counts the pulses coming through the spark plug wire.
Based on the number of received pulses, the tachometer displays the number of revolutions and engine operating time. It is made of waterproof material and weighs about 60 grams. The device operates on autonomous power supply and turns on when the engine starts.
The principle of operation of the tachometer
The operating principle of the device is based on the induction method. The tachometer is a pulse counter in the engine's electrical system. It receives information for processing from Magdino coils. The number of pulses on a magdino is determined by the number of pole pieces - their number varies from four to twelve. On the back of the tachometer there is a switch for setting the mode corresponding to the number of poles.
Some tachometers have a different operating principle. They count electrical impulses directly from the spark plug wire through the insulating material. All processed data is visible on the display. But one thing should be taken into account:
— engine speed is displayed on the screen while driving;
- engine hours - after stopping the outboard motor.
In this case, the number of hours worked can be calculated by the tachometer, both total and for certain periods of time (the latter are reset to zero).
What is a tachometer for?
Firstly, the tachometer is designed to determine the exact number of engine revolutions during its break-in. As you know, running-in is carried out for the required period of time at certain speeds specified in the engine passport. The number of revolutions diverging from the passport ones leads to a decrease in the service life of the motor.
Secondly, counting engine hours gives an idea of the total operating time of the engine. Thanks to the option of calculating the time worked per trip, the user can determine for himself how many hours a full tank of fuel is consumed.
Third, tachometer - indicator of a malfunction of the outboard motor! If the tachometer data taken at maximum and idle engine speeds differs from the passport standards, then this is a sign of some kind of problem.
Another interesting fact: changes in the speed characteristics of a motor boat. To increase the rotation speed of the motor shaft, you need to select a propeller with a smaller pitch, and vice versa. The tachometer allows you to find the optimal engine propeller.I would like to note that tachometers come in different types:
— universal (for all types of engines);
— tachometers for two-stroke engines;
— tachometers for four-stroke engines.
Installing a tachometer on a boat motor
Installing the device is not a complicated process. The installation steps are described below:
- We remove the device from the packaging and check for damage;
- Remove the cover from the engine to gain access to the spark plug wire;
- We wrap the tachometer cable (its free end), preferably four or five turns, around the spark plug wire five centimeters from the tip of the spark plug;
- We fix the turns using electrical tape or adhesive tape;
- We install the tachometer using self-tapping screws;
- Then we stretch the cable from the high voltage wire to the device;
- Tachometer installed. The on and off modes are automatic.
Developers and manufacturers of outboard motors, as a rule, do not set themselves the task of equipping the latter with any measuring instruments. This is due to the fact that boat engines are incomparable in complexity to engines for a car or motorcycle. They are much simpler and therefore do not require any measurements of operating conditions during operation.
However, the operation of outboard motors has shown that in many cases it is extremely necessary to know the real engine speed, but, unfortunately, it is impossible to determine them without a special measuring device. To determine the speed of the outboard motor in real time, a device called a “tachometer” is used.
Its use allows:
- make precise adjustments to the motor;
- choose the right one;
- select the most economical engine operating mode;
- prevent motor failure by determining whether there are malfunctions in its operation.
Types of tachometers for outboard motors
Any tachometer works as a pulse counter in the engine's electrical system, which is directly related to the speed of its crankshaft.
Unlike a car engine, a boat tachometer most often receives information not from the ignition system, but from magdino coils (“dynamo + magneto”), which on outboard motors act as a generator.
There are motors in which there is no signal from the generator. In this case, induction type tachometers are used (with their own power source).
The data obtained by the tachometer is recalculated and displays the value of the number of revolutions of the engine shaft per unit of time on the liquid crystal display screen or dial indicator.
Tachometers are classified according to several parameters and are:
- universal, that is, suitable for different types of engines;
- designed to work with a specific type of engine(two-stroke or four-stroke).
In addition, tachometers are divided into
- analog, in which the engine speed is displayed on a dial indicator;
- digital, where information about the number of engine revolutions is displayed on a digital display.
Digital tachometers can additionally be combined with other measuring instruments, for example, a counter of engine hours that a boat engine has worked.
How to choose
The existing market for tachometers for outboard motors is quite diverse and is represented by both models of well-known brands and products of unknown companies. In addition, you can find fakes on the market.
Therefore, first of all, you need to choose a reliable seller (ask where friends and acquaintances bought tachometers, look at reviews on online forums, etc.).
When choosing a tachometer, you need to pay attention to such factors and design features as:
- Tachometer functionality. There are instruments that only show the speed of a boat engine.
But there are also tachometers, which, in addition, have the ability to display the following engine parameters:
- number of engine hours;
- temperature;
- oil pressure and much more;
When choosing a tachometer, you need to proceed from the fact that many functions are only possible with special sensors, the installation and installation of which is quite complicated. Most owners of motor boats believe that the optimal choice is a tachometer with a function for calculating the number of engine hours.
This function is important when the engine is new, as well as for determining the remaining engine life. To do this, you need to choose a device that displays the number of engine hours both during one trip and their total number since the start of operation.
- Compliance of the technical characteristics of the tachometer with the parameters of the outboard motor. It is important to know here that there are tachometers that have built-in operating mode switches depending on whether the engine is used, two-stroke or four-stroke; do not have operating mode switches and are designed to work with one type of engine from different manufacturers; designed to work with engines of a specific manufacturer. For example, DF series motors are only available with 12-pole generators.
- Easy to install, install and configure.
- The tightness of the device. In most tachometers, sealing is ensured structurally, so the power source can only be replaced by disassembling the housing. However, there are tachometers that provide the ability to replace batteries without disassembling the case. This undoubtedly convenient feature can lead to water getting inside the tachometer housing, which will lead to its failure.
- Compactness of the device.
- Tachometer cost. It is of no small importance for a certain category of buyers, inducing them to choose a Chinese manufacturer. However, even among Chinese-made tachometers there are reliable models made with high quality. In addition, well-known manufacturers often offer universal, combined devices, some of the functions of which may not be needed at all, but will significantly increase the price of the tachometer.
In addition, when choosing a digital tachometer, you must ensure that you have sufficient:
- speed (frequency) of updating information on the display;
- brightness and clarity of the display of numbers on the display, especially in sunny weather.
Installation
Installing a tachometer is not difficult and is accessible to almost every motor boat user. Depending on the design, it is installed either in the dashboard of a boat or boat, or directly on the tiller (outboard) motor.
First you need to perform several simple operations:
- determine the location where the tachometer will be installed;
- determine the required wire length;
- if the tachometer is installed in the dashboard, cut a hole according to the dimensions specified in the instruction manual;
- purchase or make your own wiring harness that will connect the tachometer to the outboard motor. It is recommended not to skimp on the harness. It is better to purchase a branded harness of the required length, since its wires match the color of the connection diagram given in the instructions, and also have cable lugs and waterproof connectors. This will avoid mistakes during further installation;
- Using the installation elements included in the delivery set, secure the tachometer in a prepared place (boat dashboard, engine hood).
This completes the preparatory work and installation of the tachometer and installation work can begin.
The installation method also depends on the design of the tachometer:
- If the tachometer does not have its own power source, then it reads pulses directly from the magneto coils, where the cable must be connected.
- If the tachometer is equipped with its own power source, then to connect it you need to twist the connecting harness around the spark plug wire with several turns. The number of turns and the distance to the spark plug are specified in the instruction manual (approximately 3 to 6 turns at a distance of 4 cm from the spark plug). Then the harness is connected to the tachometer terminals.
The connecting cable must be laid in such a way that it does not come into contact with hot or moving parts of the motor. All connections must be made according to the tachometer connection diagram. If all connections are made correctly, then after starting the engine, the tachometer immediately begins to show the number of revolutions.
In order for the indicated engine speed to correspond to reality, you need to adjust the tachometer.
Settings
In general, setting up a tachometer comes down to setting its operating modes, which correspond to the operating modes of the connected motors.
Therefore, if:
- The tachometer is designed to work with motors of the same type from different manufacturers, or their different types from only one manufacturer (all this is indicated in the accompanying documentation), then when starting the engine, the tachometer must show a fairly accurate number of revolutions. The accuracy of the readings is checked by comparing the engine speed at idle, indicated in the operating manual, with the tachometer readings when the engine is running in the same mode. If the indicators do not match, you can bring them into compliance following the instructions.
- The tachometer is universal, then you need to set the operating mode selector to the position corresponding to the number of pulses per revolution of the engine crankshaft - if the device is connected to a magneto. In this case, the type of engine does not matter, and the number of pulses is indicated in a special table attached to the instruction manual, and the type of engine (two-stroke or four-stroke) - if the device is connected to a spark plug wire. The number of cylinders does not matter.
Setting the operating modes of tachometers is carried out only with the outboard engine turned off.
Review of popular models
Manufacturers of outboard motors, as a rule, do not make measuring instruments for them. This task is assigned to partner companies. For example, Teleflex Marine produces a large number of tachometers with the Mercury logo. At the same time, it also produces Osculati tachometers and branded Teleflex.
Also, a number of other companies (China, Taiwan) produce a large number of tachometers with Yamaha and Suzuki logos. Therefore, professionals suggest not focusing on the “native” brand of tachometer and, when choosing it, be guided by practical expediency.
Let's consider several of the most popular models of tachometers for outboard motors:
- Yamaha. The digital multifunctional tachometer 6Y8T-8350T-11-BK is housed in a waterproof housing. Designed to fit into a standard 86mm instrument panel hole and is used with Yamaha engines from F50 and above. The display shows the current and maximum engine speed, as well as the number of engine hours. The cost of the tachometer is 23,615 rubles.
Cost – 23615 rubles. - Mercury. Flagship analog tachometer (0-8000 rpm) is designed for installation on all Mercuri engines. It has a waterproof case with anti-fog glass, as well as a pointer dial. The price of the tachometer is 5620 rubles.
Price – 5620 rub. - Suzuki. Analog tachometer for DF9.9-30/DT25-40 engines – installed in a standard hole in the boat’s dashboard (86 mm). It has anti-fog glass and shows up to 7000 engine rpm. It does not have an operating mode selector, since all Suzuki DF/DT series engines are equipped with 12-pole generators. Its price is 4400 rubles.
Price – 4400 rub. 
