A tachometer is a device that shows the speed of the engine crankshaft. Installed on almost all modern car models. It helps the driver to correctly operate the engine, since the traction and power characteristics of it (the engine) significantly depend on the crankshaft speed. In the absence of such a device on the panel or a malfunction of the standard tachometer, you can install and connect a remote tachometer to both a gasoline and a diesel engine.
It is necessary
tachometer, electrical circuit of the car, a set of wrenches and screwdrivers, wire, electrical tape
Instructions
Step 1
The principle of operation of all electronic and electromechanical tachometers is that they read the number of pulses entering the ignition coil (in gasoline engines) or from the “W” terminal of the generator (in diesel engines). The number of pulses coming from this output of the generator (at the same engine speed) is approximately 6 times the number of pulses entering the ignition coil. Therefore, when purchasing a tachometer, be sure to consult your dealer if this device will work correctly on your car. There are universal tachometers in which a special switch is installed that allows you to connect the device to engines of different types (diesel - gasoline, 2, 4, 5, 6, 8 cylinders).
Step 2
To connect a tachometer in a car with an ignition system, install and secure it at a convenient place for you on or near the dashboard. Connect the negative lead (black) to the ground (body) of the vehicle. Connect the plus of the power supply (red) to the terminal of the ignition lock at which a voltage of 12 volts appears when the ignition system is turned on. Connect the third wire (tachometer input) to the ignition coil terminal that is connected to the distributor breaker (contact ignition system) or to the switch (contactless ignition system). On many models of external tachometers, the device is backlit at night. Connect the tachometer backlight wire to the vehicle sizing switch.
Step 3
On a diesel engine, connect the tachometer input lead to the “W” terminal on the generator. If your generator does not have such a terminal, bring it out with a well-insulated wire. To do this, remove and disassemble the generator. Three wires go from the winding to the built-in generator rectifier. Connect to any of these three wires and carefully route the wire out. Assemble the generator, making sure that the wire does not touch moving parts.
