OMC Evinrude Johnson 3" Sys Tach/Retro

The OMC Evinrude Johnson 3" System Tachometer (Retro Style) is a genuine OEM marine gauge designed to monitor engine RPM on Evinrude and Johnson outboards. Known commonly as a 3" System Tach/Retro, this instrument is part of the System Check™ gauge lineup and features a classic retro design that blends well with both vintage and modern dash panels.

🔧 Product Description

• Name: OMC Evinrude Johnson 3" System Tachometer - Retro Style

• Gauge Size: 3 inches (standard dashboard cutout size)

• Style: Retro (classic white or black face, chrome or stainless bezel)

• Function: Displays engine RPM (usually up to 7000 or 8000 RPM range)

• Compatibility:

  • Works with most 2-stroke and 4-stroke Johnson/Evinrude outboards

  • Integrates with System Check harnesses to show engine alerts (oil, temp, check engine, etc.)

• Features:

  • RPM Display

  • Integrated System Check warning lights (LED indicators)

  • Adjustable pole settings for different alternator pulse counts

  • Red backlighting or white depending on model variant

• Part Number Examples (varies slightly by bezel and color):

  • 778881

  • 779174

  • 764339 (I-Command style retro variant)

✅ Why It’s Used

This tach is essential for:

• Monitoring engine speed for proper performance

• Preventing over-revving

• Providing real-time alerts via System Check (oil, overheating, battery, etc.)

🛠️ Installation Notes

• Installs into a standard 3" gauge cutout

• Connects via a 4-pin System Check harness

• May require a sender or specific harness adapter depending on model/year