The speedometer is a tool that indicates the revolutions per minute made by a running engine. Most cars with automatic transmissions do not have a speedometer, as it is used visually to indicate when it is time to change gear. If your car does not have one, you should consider fitting one to keep an eye on your engine performance. Here is some information.
Steps
Part 1 of 2: Where to Start
Step 1. Get a speedometer with its connectors
You can buy a new one, usually the cost is between 20 and 40 euros, or get a second-hand one, certainly cheaper.
You will also need to use electrical connectors for the installation, which you can buy at any electrical sales center. The connection cables are usually between 16 and 18 in diameter; make sure you buy a suitable connector
Step 2. Adjust the speedometer according to the engine displacement
The new models work with 4, 6 or 8 cylinder engines; the relevant adjustments are located on the rear of the speedometer, under the cover.
- Adjust the displacement setting according to your engine. Put the cover back on the speedometer carefully, so as not to damage the internal parts of the meter. If necessary, use a screwdriver.
- There are usually two switches - at 1 and at 2. In most cases, the lower position in both is used for the 4-cylinder engine and the upper position for the 8-cylinder. In a 6-cylinder engine, one switch has to be pushed down and one pushed up. If you buy a new speedometer, read the instructions to make sure.
Step 3. Locate the power cord
Depending on the engine, you should find one DC and one AC lead, plus other cables for starter, lights, and other functions. It is important to identify the right cables to connect to the speedometer; to be sure you can use a tester and take a look at your car's manual.
It is important to bear in mind that some new generation speedometers are incompatible with the spark plug power cables, and it could be dangerous to attempt to connect them without considering the relevant installation instructions
Step 4. Check the connection
Before fixing the unit to the dashboard, check the connections and operation of the unit with the engine running. Better not to start drilling holes in the dashboard until you are sure the connections are in place. After connecting the appliance correctly, you should be able to see the revolutions per minute made by the engine when it is running.
- Connect the appliance to the ground. Connect the speedometer ground wire to the engine ground. It does not have to be connected directly to the battery. Most of the frames are connected to the battery via rather sturdy cables. Better to connect the ground to one of these cables.
- Connect the speedometer power supply. The speedometer power cable should run from the dashboard through a grommet to reach the engine compartment. This connection point may vary from car to car.
Part 2 of 2: Installing the Speedometer
Step 1. Choose an installation location
Most dashboards are not designed for mounting equipment, so installation on the steering column is usually recommended.
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Make holes in the steering column and use the support provided in the package. If you have purchased a new speedometer you will find in the box the instructions and everything you need to complete the installation.
Install a Tachometer Step 5Bullet1 -
Mount the speedometer to the steering column. Get a holder that can anchor the speedometer to the steering column. Secure the steering mount. A simple U-shaped stand should suffice.
Install a Tachometer Step 5Bullet2
Step 2. Install the speedometer
Connect the speedometer power cable to a 12 volt light system cable.
Connect the speedometer backlight. Locate a 12-volt socket in the lighting switch box. Connect the speedometer light wire
Step 3. Protect the wire with a gasket
It is advisable to protect the cables with a rubber gasket in the path between the dashboard and the engine compartment. If a wire rubs against a metal part, it could result in a small combustion or fire. It is always better to take the necessary precautions and apply protection, which has a low cost and can be installed in a short time.
Step 4. Install an indicator light if possible
This light will remind you when you need to change gear. Not all speedometers have this device. If your chosen model has it, follow the installation instructions. The speedometer light cannot be adjusted with the engine running.
