What To Know
- Whether due to incorrect readings, maintenance procedures, or simply a desire for a fresh start, resetting the tachometer is a straightforward task that can be accomplished with a few simple steps.
- With the wiring harness disconnected, use a small screwdriver to gently press the reset button located on the back of the tachometer.
- Use a multimeter to measure the voltage output of the sender unit while the engine is running at a known RPM.
Your Yamaha outboard tachometer, a crucial instrument for monitoring engine speed, may occasionally require a reset to ensure accurate readings. Whether due to incorrect readings, maintenance procedures, or simply a desire for a fresh start, resetting the tachometer is a straightforward task that can be accomplished with a few simple steps.
Step 1: Gather the Necessary Tools
Before embarking on the reset process, make sure you have the following tools at hand:
- Small screwdriver
- Wrench or pliers
- Multimeter (optional)
Step 2: Safety First – Disconnect the Battery
To ensure a safe and risk-free reset procedure, always begin by disconnecting the negative terminal of your boat’s battery. This will prevent any electrical hazards or accidental engine starts.
Step 3: Locate the Tachometer Sender Unit
The tachometer sender unit, which transmits signals to the tachometer, is typically located near the flywheel or crankshaft. Identify the sender unit and disconnect its wiring harness.
Step 4: Reset the Tachometer
With the wiring harness disconnected, use a small screwdriver to gently press the reset button located on the back of the tachometer. Hold the button for a few seconds until the needle returns to zero.
Step 5: Reconnect the Battery and Sender Unit
Once the tachometer is reset, reconnect the negative battery terminal. Then, reconnect the wiring harness to the tachometer sender unit.
Step 6: Calibrate the Tachometer (Optional)
If desired, you can calibrate the tachometer to ensure accurate readings. Use a multimeter to measure the voltage output of the sender unit while the engine is running at a known RPM. Adjust the calibration screw on the back of the tachometer until the tachometer reading matches the actual RPM.
Step 7: Test and Verify
Start the engine and observe the tachometer reading. It should now display accurate engine speed information. If not, repeat the calibration steps or consult a qualified marine technician for assistance.
Troubleshooting Common Issues
Tachometer Not Reading Correctly
- Verify that the tachometer sender unit is properly connected and receiving power.
- Check the wiring harness for any damage or loose connections.
- Calibrate the tachometer using the steps outlined above.
Tachometer Needle Fluctuating or Jumping
- Inspect the tachometer sender unit for any damage or loose connections.
- Check the ground wire connection between the tachometer and the engine.
- Replace the tachometer sender unit if necessary.
Tachometer Not Resetting
- Ensure that you are pressing the reset button located on the back of the tachometer.
- If the button is stuck or unresponsive, consult a qualified marine technician for assistance.
What You Need to Know
Q: Why should I reset my Yamaha outboard tachometer?
A: Resetting the tachometer ensures accurate engine speed readings, eliminates incorrect readings, and prepares it for maintenance procedures.
Q: How often should I reset my tachometer?
A: Resetting the tachometer is not a regular maintenance task. However, it is recommended to reset it if you experience incorrect readings or after performing maintenance on the engine or tachometer system.
Q: Can I reset the tachometer while the engine is running?
A: No, always disconnect the battery and stop the engine before resetting the tachometer.
