# 8M0068784 Mercury Oil Pressure Switch | Genuine Used Part

🔧 Product Description

  

Genuine Mercury MerCruiser 80 PSI Oil Pressure Sender - Part Number: 8M0068784

  

A genuine Mercury MerCruiser electric oil-pressure sender for marine engines fitted with an 80 PSI dashboard gauge.

  

The supplied title described this component as a pressure switch; however, 8M0068784 is a variable-resistance gauge sender. It uses a single 10-32 stud terminal and a 1/8-inch-27 NPT thread.

  

⚙️ Key Features

  

• Genuine Mercury MerCruiser oil-pressure sender

• Correct part number 8M0068784

• 0-80 PSI gauge range

• Approximately 0-300 ohm variable-resistance output

• 1/8-inch-27 NPT mounting thread

• Single 10-32 stud electrical terminal

  

🔄 Supersession & Cross Reference

  

OEM Supersession Chain:

  

• 8M0068784 → Supersedes 815425T

• 815425T → Related to earlier 815425, 90806 and 90806A1 references

  

OEM / Related Numbers:

  

• Mercury / MerCruiser 8M0068784

• Mercury 815425T

• Mercury 815425

• Mercury 90806 / 90806A1

• Mercury 34623

• Volvo Penta / OMC 3857532

• OMC 3853800 / 0982650 / 0172127

• Crusader 700425

• Pleasurecraft R02001

  

Aftermarket / Verified Equivalents:

  

• Sierra: 18-5899

• Faria: 90512

• Datcon: 02504-00

• Pro Marine: 65899

• Redline: 5899

• Stewart Warner: 279-A

• VDO: 360 801

• Veethree / SeaStar: IA15001

• Generic 80 PSI, 1/8-27 NPT marine sender matching the original resistance curve

  

🚤 Compatibility

  

Commonly used on:

  

• MerCruiser 3.0L inline-four petrol engines

• MerCruiser 4.3L V6 engines

• MerCruiser 5.0L and 5.7L V8 engines

• MerCruiser 7.4L and 8.2L V8 engines

• Volvo Penta GM-based petrol engines

• OMC Cobra, Crusader and Pleasurecraft engines using the listed cross-reference

  

• Gauge Range: 0-80 PSI

• Electrical System: 12V DC

• Fitment Requirement: Must be used with a gauge sender circuit, not an on/off warning-switch circuit

  

🔌 Function

  

The sender changes electrical resistance as engine-oil pressure rises and falls. The dashboard gauge converts the resistance into an oil-pressure reading.

  

Common signs of failure:

  

• Gauge remains at zero or full scale

• Reading fluctuates despite stable mechanical pressure

• Oil leaks around the threaded body

• Sender terminal is loose or corroded

• Gauge reading is inaccurate because the wrong resistance curve is fitted

  

📦 Condition

  

• Genuine used part

• Removed from running engine where applicable

• In good working condition unless otherwise stated

• Test sender resistance and inspect the thread before installation

## Details

- **Price:** 2.5 AUD
- **Vendor:** Sawley's Auto and Marine
- **Tags:** Sawley’s AAM Used Parts – Oil Pumps & Components | Engine Lubrication Systems

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 2.50 AUD | In stock |

## Images

- 8M0068784 Mercury Oil Pressure Switch | Genuine Used Part
- 8M0068784 Mercury Oil Pressure Switch | Genuine Used Part
- 8M0068784 Mercury Oil Pressure Switch | Genuine Used Part
- 8M0068784 Mercury Oil Pressure Switch | Genuine Used Part
- 8M0068784 Mercury Oil Pressure Switch | Genuine Used Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/8m0068784-mercury-oil-pressure-switch-genuine-used-part)
> Updated: 2026-07-20