# 420856504 Seadoo Vent Valve | Genuine Used Part

🔧 Product Description

  

Genuine Sea-Doo Vent Valve Ass'y - Part Number: 420856504

  

This genuine Sea-Doo vent valve assembly is used in the cylinder head and crankcase ventilation system on selected supercharged Sea-Doo 4-TEC engines. It helps control engine breathing and oil vapour flow through the factory vent system.

  

⚙️ Key Features

  

• Genuine Sea-Doo vent valve assembly

• OEM part number 420856504

• Engine ventilation / breather valve component

• Supersedes earlier OEM vent valve reference 420856502

• Direct-fit OEM component for listed 4-TEC cylinder head ventilation assemblies

  

🔄 Supersession & Cross Reference

  

OEM Supersession Chain:

  

• 420856504 → Supersedes 420856502

• 420856502 (earlier OEM reference)

  

OEM / Related Numbers:

  

• 420856504

• 420856502

  

Aftermarket / Verified Equivalents:

  

• WSM: replacement vent valve assembly to suit 420856504 / 420856502 applications

  

🚤 Compatibility

  

Commonly used on:

  

• Sea-Doo 4-TEC cylinder head ventilation assemblies

  

Typically suits:

  

• Engine models:

• 2009 GTX Limited iS 255 — Cylinder Head

• 2009 RXT iS 255 — Cylinder Head

• 2010 GTX iS 215 — Cylinder Head

• 2010 GTX Limited iS 260 — Cylinder Head

• 2010 RXT 215 — Cylinder Head

• 2010 RXT iS 260 — Cylinder Head

• 2010 RXT-X 260 & X RS — Cylinder Head

• 2010 WAKE PRO 215 — Cylinder Head

• 2011 GTX 215 — Cylinder Head

• 2011 GTX iS 215 — Cylinder Head

• 2011 GTX Limited iS 260 — Cylinder Head

• 2011 RXT 260 & RS — Cylinder Head

• 2011 RXT iS 260 — Cylinder Head

• 2011 RXT-X 260 & RS — Cylinder Head

• 2011 WAKE PRO 215 — Cylinder Head

• 2012 GTX 215 — Cylinder Head

• 2012 GTX Limited iS 260 — Cylinder Head

• 2012 RXT 260 / RXT-X 260 — Cylinder Head

• 2012 WAKE PRO 215 — Cylinder Head

  

• HP Range: Approximately 215HP - 260HP

• Engine Type: Sea-Doo Rotax 1503 4-TEC Supercharged Cylinder Head / Ventilation System

• Year Range: Approximately 2009 - 2012

  

🔌 Function

  

The vent valve helps regulate crankcase and cylinder head ventilation, allowing vapour flow through the breather system while helping control oil carry-over.

  

Common signs of failure:

  

• Excess oil vapour in intake system

• Oil residue around breather hoses

• Poor crankcase ventilation

• Split or damaged valve body

• Rough running caused by breather-system leakage

  

📦 Condition

  

• Genuine used part

• Removed from running engine where applicable

• In good working condition unless otherwise stated

## Details

- **Price:** 45.0 AUD
- **Vendor:** Sawley's Auto and Marine
- **Tags:** Sawley’s AAM Used Parts – Sea-Doo Parts | Jet Ski Parts & Components

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 45.00 AUD | In stock |

## Images

- 420856504 Seadoo Vent Valve | Genuine Used Part
- 420856504 Seadoo Vent Valve | Genuine Used Part
- 420856504 Seadoo Vent Valve | Genuine Used Part
- 420856504 Seadoo Vent Valve | Genuine Used Part
- 420856504 Seadoo Vent Valve | Genuine Used Part
- 420856504 Seadoo Vent Valve | Genuine Used Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/420856504-seadoo-vent-valve-genuine-used-part)
> Updated: 2026-07-02