1. Product Overview
The Geloo 85MM RPM Tachometer Gauge is designed to accurately display the rotation speed of an engine. This gauge is suitable for a wide range of applications, including cars, trucks, boats, diesel generator engines, gasoline engines, construction machinery, and agricultural machinery.
Key Features:
- Wide Compatibility: Works with various tacho RPM sensors and engine types (4, 6, 8, 10, 12 cylinder gas engines, and diesel engines).
- Durable Construction: Made with a 316 stainless steel bezel, PVC, ABS, and curved glass for long-lasting performance.
- Environmental Resistance: Features an IP67 waterproof and dustproof rating, along with anti-fog properties, ensuring clear readings in challenging conditions.
- Multi-Color Backlight: Offers 7 backlight colors (red, green, blue, white, yellow, cyan, purple) with an automatic cycling mode.
- Wide Voltage Range: Operates on 9-32V DC power.
Figure 1: Front view of the Geloo 85MM RPM Tachometer Gauge.
2. Specifications
| Feature | Specification |
|---|---|
| Brand | Geloo |
| Material | Glass, Stainless Steel |
| Dimensions (L x W x H) | 4.88 x 4.76 x 3.11 inches |
| Item Weight | 0.55 Pounds |
| Number of Items | 1 |
| Operating Voltage | 9-32V DC |
| RPM Range | 0-6000 RPM |
| Installation Hole Diameter | 85mm (3 3/8 inches) |
| Required Backyard Space | 55mm |
| Waterproof Rating | IP67 |
Figure 2: Product dimensions for installation planning.
3. Installation
Proper installation is crucial for the accurate and reliable operation of your tachometer gauge. Follow these steps carefully:
3.1 Mounting the Gauge
- Prepare the Panel: Identify a suitable location on your dashboard or panel. You will need to open a hole with a diameter of 85mm (3 3/8 inches).
- Check Clearance: Ensure there is at least 55mm of clear space behind the panel for the gauge body and wiring connections.
- Insert and Secure: Carefully insert the tachometer gauge into the prepared hole. Use the provided mounting ring and nuts to secure the gauge firmly in place.
3.2 Wiring Connections
Connect the wires from the gauge to your vehicle's electrical system as follows:
- Black Wire: Connect to Ground (-).
- Red Wire: Connect to 9-32VDC Power (+).
- Blue Wire: Connect to the RPM Signal source (e.g., ignition coil, alternator 'W' terminal, or dedicated RPM sensor output).
- Yellow Wire: Connect to Backlight Power (+). This can be connected to the Red wire for constant backlight or to a switched power source for controlled illumination.
Figure 3: Detailed wiring diagram and speed ratio settings.
3.3 Speed Ratio Settings
The tachometer requires a specific speed ratio setting to accurately display RPM based on your engine type. Refer to the table below to determine the correct setting for your engine:
| Inboard or Gas Engine | Diesel Engine | Outboard Engine | ||
|---|---|---|---|---|
| Cylinder | Speed Ratio | Speed Ratio = Gear Number | Poles | Speed Ratio |
| 4 | 2 | Speed ratio is determined by the gear number of the diesel engine. | 4 | 2 |
| 6 | 3 | 6 | 3 | |
| 8 | 4 | 8 | 4 | |
| 10 | 5 | 10 | 5 | |
| 12 | 6 | 12 | 6 | |
Note: The speed ratio setting is typically adjusted via a button or switch on the back of the gauge, or through a specific sequence of button presses. Refer to the small instruction sheet included with the product for precise adjustment procedures.
Figure 4: Example of the tachometer gauge installed in a boat dashboard.
4. Operation
Once installed and wired correctly, the tachometer gauge will power on with your vehicle's ignition. The needle will indicate the engine's RPM (Revolutions Per Minute).
4.1 Backlight Color Adjustment
The gauge features multiple backlight colors for enhanced visibility and personalization. To change the backlight color:
- Locate the small button on the back of the gauge.
- Short press the button to cycle through the available colors: Red (default) → Green → Blue → White → Yellow → Cyan → Purple.
- After cycling through all colors, the next press will activate the automatic mode, which automatically switches the backlight color every 1 minute.
Figure 5: Backlight color options and the adjustment button on the rear of the gauge.
4.2 Product Demonstration Video
Video 1: A demonstration of the Geloo 85MM RPM Tachometer Gauge, including its waterproof capabilities and general appearance.
5. Maintenance
To ensure the longevity and optimal performance of your Geloo Tachometer Gauge, follow these simple maintenance guidelines:
- Cleaning: Use a soft, damp cloth to clean the gauge face and bezel. Avoid abrasive cleaners or solvents that could damage the materials or finish.
- Environmental Protection: The gauge is designed with an IP67 waterproof and dustproof rating. This means it is protected against dust ingress and temporary immersion in water (up to 1 meter for 30 minutes). While durable, avoid prolonged submersion or high-pressure water jets.
- Inspection: Periodically check the wiring connections for any signs of corrosion or looseness. Ensure the mounting remains secure.
Figure 6: The gauge features IP67 dustproof and waterproof protection.
6. Troubleshooting
If you encounter issues with your tachometer gauge, consider the following troubleshooting steps:
- Inaccurate RPM Readings:
- Verify that the speed ratio setting is correctly configured for your engine's cylinder count or pole number (refer to Section 3.3). Incorrect settings are a common cause of inaccurate readings.
- Check the Blue RPM Signal wire connection. Ensure it is securely connected to a reliable RPM signal source and that the signal is clean and consistent.
- No Power or Display:
- Confirm that the Red (9-32VDC Power) and Black (Ground) wires are correctly and securely connected to a power source within the specified voltage range.
- Check for any blown fuses in the power circuit.
- Backlight Not Working or Stuck:
- Ensure the Yellow (Backlight) wire is properly connected to a power source.
- Try short-pressing the button on the back of the gauge multiple times to cycle through colors and exit any potential automatic mode (refer to Section 4.1).
- Gauge Not Responding:
- Temporarily disconnect and reconnect power to the gauge to perform a soft reset.
- Inspect all wiring for damage, pinches, or loose connections.
7. Warranty and Support
Geloo is committed to providing high-quality products. Each tachometer gauge undergoes strict quality inspection before leaving the factory to ensure reliability and performance.
If you have any questions about the product, require assistance with installation, or encounter any issues that cannot be resolved using the troubleshooting guide, please contact Geloo customer support. Provide your product model and a detailed description of the issue to receive prompt assistance.
