# 859678A1 895285A04 Mercury Speedometer | Genuine Used Part

🔧 Product Description

  

Genuine Mercury Quicksilver Flagship 10-80 MPH Speedometer - Part Number: 79-859678A1

  

A genuine used Mercury Quicksilver Flagship pitot speedometer with a 10-80 MPH scale for higher-speed marine applications.

  

The black-face instrument uses water pressure from a compatible pitot pickup to display vessel speed and does not require an electronic speed sensor.

  

⚙️ Key Features

  

• Genuine Mercury Quicksilver OEM Flagship speedometer

• Correct Mercury part number 79-859678A1

• 10-80 MPH speed range

• Black face, blue graduations and black bezel

• Complete 825285A1 / 827875A1 / 859678A1 / 895285A04 family

  

🔄 Supersession & Cross Reference

  

OEM Supersession Chain:

  

• 79-895285A04 → Supersedes 79-859678A1

• 79-859678A1 → Supersedes 79-827875A1

• 79-827875A1 → Supersedes 79-825285A1

• 79-825285A1 earlier OEM 80 MPH speedometer reference

  

OEM / Related Numbers:

  

• 79-859678A1

• 859678A1

• 79859678A1

• 79-827875A1

• 827875A1

• 79-825285A1

• 79-895285A04

• 895285A04

  

Aftermarket / Verified Equivalents:

  

• Sierra: 63076P - 20-80 MPH pitot speedometer

• Sierra: 62723P - Premier Pro 20-80 MPH pitot speedometer

  

🚤 Compatibility

  

Commonly used on:

  

• Mercury Flagship-series high-speed boat dashboards

• Pitot-pressure systems using a compatible transom or gearcase pickup

  

Typically suits:

  

• Engine models:

• Performance Mercury and Mariner outboard-powered boats with a pitot pickup

• MerCruiser Alpha and Bravo sterndrive boats using a compatible gearcase pitot pickup

• Inboard performance boats fitted with an independent pitot pickup

  

• HP Range: Not engine-specific

• Engine Type: Outboard, sterndrive or inboard performance boat with pitot-pressure speed system

• Year Range: Approximately 1990s - 2000s

  

🔌 Function

  

The speedometer converts water pressure created at the pitot pickup into an indicated MPH reading. A clear pickup, correctly routed hose and airtight fittings are required for accurate operation.

  

Common signs of failure:

  

• Gauge does not register speed

• Pitot pickup or lower-unit passage is blocked

• Pressure hose leaks, kinks or disconnects

• Reading fluctuates because of air or water trapped in the line

• Internal diaphragm or needle mechanism fails

  

📦 Condition

  

• Genuine used part

• Removed from running engine where applicable

• In good working condition unless otherwise stated

## Details

- **Price:** 25.0 AUD
- **Vendor:** Sawley's Auto and Marine
- **Tags:** Sawley’s AAM Used Parts – Gauges | Marine Gauges & Instrumentation

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 25.00 AUD | In stock |

## Images

- 859678A1 895285A04 Mercury Speedometer | Genuine Used Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/859678a1-895285a04-mercury-speedometer-genuine-used-part)
> Updated: 2026-07-18