# 8M0204714 Mercury MerCruiser 8M0204714 Thermostat Gasket | Genuine Quicksilver OEM Part

🔧 Product Description

  

Genuine Quicksilver Thermostat Gasket - Part Number: 27-8M0204714

  

A genuine Quicksilver thermostat gasket used in selected Mercury and Mariner outboard thermostat and cylinder head cooling-system assemblies. This gasket seals the thermostat or thermostat cover interface, helping maintain correct cooling water flow and temperature regulation.

  

⚙️ Key Features

  

• Genuine Quicksilver OEM thermostat gasket

• Correct Mercury part number 27-8M0204714

• Cross-references with earlier 27-62386 and 27-62386001 gasket references

• Used across selected 2-stroke, DFI / OptiMax, EFI and small outboard thermostat assemblies

• Important replacement gasket during thermostat or cylinder head service

  

🔄 Supersession & Cross Reference

  

OEM Supersession Chain:

  

• 27-8M0204714 current OEM thermostat gasket reference

• 27-8M0204714 → replaces / cross-references with 27-62386001

• 27-62386001 → related to 27-62386 earlier thermostat gasket reference

  

OEM / Related Numbers:

  

• 27-8M0204714

• 8M0204714

• 278M0204714

• 27-62386001

• 27-62386

• 27-62386B

  

Aftermarket / Verified Equivalents:

  

• Sierra: 18-0182

• GLM: 30610

  

🚤 Compatibility

  

Commonly used on:

  

• Mercury / Mariner thermostat and thermostat cover gasket applications

• Mercury DFI / OptiMax 1.5L and 2.5L cooling-system gasket assemblies

  

Typically suits:

  

• Engine models:

• Mercury 15HP - serial 0T980000 to 0T999999

• Mercury 15HP - serial 1B000001 and up

• Mercury 15HP Marathon - serial 1B000001 and up

• Mercury 15HP SeaPro - serial 1B000001 and up

• Mercury 20 Jet - serial 1B000001 and up

• Mercury 40 Jet - serial 0T980000 and up

• Mercury 55HP 3-cylinder - serial 0T980000 and up

• Mercury 75HP 3-cylinder - serial 0T980000 to 0T999999

• Mercury 75HP 3-cylinder - serial 1B000001 and up

• Mercury 80 Jet - serial 0T980000 to 0T999999

• Mercury 80 Jet - serial 1B000001 and up

• Mercury 90HP 3-cylinder - serial 0T980000 to 0T999999

• Mercury 90HP 3-cylinder - serial 1B000001 and up

• Mercury 75 DFI 1.5L 3-cylinder - serial 0T980000 to 1B226999

• Mercury 75 DFI 1.5L 3-cylinder - serial 1B227000 to 1B417701

• Mercury 75 DFI 1.5L 3-cylinder - serial 1B417702 to 1B736885

• Mercury 75 DFI 1.5L 3-cylinder - serial 1B736885 and up

• Mercury 80 Jet DFI 1.5L 3-cylinder - serial 1B586067 to 1B736885

• Mercury 80 Jet DFI 1.5L 3-cylinder - serial 1B736885 and up

• Mercury 90 DFI 1.5L 3-cylinder - serial 0T801000 to 1B226999

• Mercury 90 DFI 1.5L 3-cylinder - serial 1B227000 to 1B417701

• Mercury 90 DFI 1.5L 3-cylinder - serial 1B417702 to 1B736885

• Mercury 90 DFI 1.5L 3-cylinder - serial 1B736885 and up

• Mercury 115 DFI 1.5L 3-cylinder - serial 0T801000 to 1B226999

• Mercury 115 DFI 1.5L 3-cylinder - serial 1B227000 to 1B417701

• Mercury 115 DFI 1.5L 3-cylinder - serial 1B417702 to 1B736885

• Mercury 115 DFI 1.5L 3-cylinder - serial 1B736885 and up

• Mercury 115 Pro XS 1.5L 3-cylinder - serial 1B751825 and up

• Mercury 125 DFI 1.5L 3-cylinder - serial 1B736885 and up

• Mercury V-135 DFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-135 DFI 2.5L - serial 1B227000 to 1B417701

• Mercury V-135 DFI 2.5L - serial 1B417702 and up

• Mercury V-150 DFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-150 DFI 2.5L - serial 1B227000 to 1B417701

• Mercury V-150 DFI 2.5L - serial 1B417702 and up

• Mercury V-175 DFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-175 DFI 2.5L - serial 1B227000 to 1B417701

• Mercury V-175 DFI 2.5L - serial 1B417702 and up

• Mercury V-150 EFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-150 EFI 2.5L - serial 1B227000 and up

• Mercury V-200 EFI 2.5L - serial 0T801000 to 1B226999

• Mercury V-200 EFI 2.5L - serial 1B227000 and up

  

• HP Range: broad outboard thermostat-family usage where specified by diagram

• Engine Type: Mercury / Mariner 2-stroke, DFI / OptiMax and EFI outboard

• System Type: Thermostat gasket / cooling system seal

  

🔌 Function

  

The thermostat gasket seals the thermostat housing or cover joint so the cooling system can regulate temperature without leakage or pressure loss.

  

Common signs of failure:

  

• Water leakage around thermostat cover

• Overheating from poor thermostat sealing

• Salt build-up around housing joint

• Torn gasket during thermostat service

• Thermostat cover will not seal after removal

  

📦 Condition

  

• Genuine Quicksilver part

• Brand new

• Supplied in original or equivalent packaging

## Details

- **Price:** 4.1 AUD
- **Vendor:** Quicksilver
- **Tags:** Quicksilver Marine Parts | Oils Service Kits & Engine Components

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 4.10 AUD | In stock |

## Images

- 8M0204714 Mercury MerCruiser 8M0204714 Thermostat Gasket | Genuine Quicksilver OEM Part

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> Source: [Sawley's Auto and Marine](www.sawleysautoandmarine.com.au/products/8m0204714-mercury-mercruiser-8m0204714-thermostat-gasket-genuine-quicksilver-oem-part)
> Updated: 2026-05-17