# 3C8650183 Tohatsu Marine Gasket | Genuine OEM Outboard Part

🔧 Product Description

  

Genuine Tohatsu / Nissan Water Pump Case Gasket - Part Number: 3C8-65018-3

  

A genuine Tohatsu/Nissan water-pump case gasket for the three-cylinder 40 HP and 50 HP pump assembly. The compact service number 3C8650183 corresponds to OEM part 3C8-65018-3 and supersedes earlier gasket revisions.

  

⚙️ Key Features

  

• Genuine Tohatsu/Nissan formed pump-case gasket

• Seals the pump liner/housing assembly to the lower-unit surface

• Correct coolant-port and bolt-hole alignment

• Single-use gasket recommended whenever the pump assembly is removed

  

🔄 Supersession & Cross Reference

  

OEM Supersession Chain:

  

• 3C8-65018-3 / 3C8650183M → current gasket reference

• 3C8-65018-2 → preceding revision

• 3C8-65018-1 / 3C8650181M → earlier gasket superseded to 3C8650183M

  

OEM / Related Numbers:

  

• 3C8650183

• 3C8650183M

• 3C8-65018-3

• 3C8-65018-2

• 3C8-65018-1

• 3C8650181M

  

Aftermarket / Verified Equivalents:

  

• Aftermarket 3C8-65018-3 pump-case gasket

• Mercury cross-reference family: 27-16158-3 on applicable Tohatsu-built engines

  

🚤 Compatibility

  

Commonly used on:

  

• Tohatsu M40D and M40D2

• Tohatsu M50D and M50D2

• Nissan NS40D2 and NS50D2

• Selected MD40/MD50 or Tohatsu-built Mercury/Mariner pump assemblies only where 3C8-65018-3 is specified

  

Typically suits:

  

• HP Range: 40-50 HP

• Engine / System Type: Three-cylinder two-stroke/TLDI lower-unit water pump, application dependent

• Year Range: Approximately 2002 onward, pump revision dependent

• Serial / Identification Range: Confirm the pump housing and gasket profile. Earlier and later 3C8/3T5 pump housings can require different matched liners and gaskets.

  

🔌 Function

  

Seals the water-pump case to prevent cooling-water pressure loss around the pump base.

  

Common signs replacement or service is required:

  

• Water leakage around the pump case

• Weak pump output after reassembly

• Gasket is torn, compressed or stuck to the housing

• Corrosion or scoring is present on the gasket surface

  

📦 Condition

  

• Genuine Tohatsu / Nissan OEM gasket, brand new.

• Brand new

• Supplied in manufacturer or equivalent protective packaging

## Details

- **Price:** 8.4 AUD
- **Vendor:** Tohatsu
- **Tags:** Tohatsu Outboard Parts | Marine Engine Components & Spares

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 8.40 AUD | In stock |

## Images

- 3C8650183 Tohatsu Marine Gasket | Genuine OEM Outboard Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/3c8650183-gasket)
> Updated: 2026-08-01