Name: Yamaha Outboard Gear Case Oil Drain Washer Seal 90430-08020 6HP-300HP 4Boats
Brand: Yamaha
SKU: 90430-08020
Price: 1.99 GBP
Availability: InStock
Rating: 5.0 (1 reviews)

Yamaha Outboard 6-300hp Gear Case Oil Drain Washer Seals Replaces 90430-08020-0 - 4Boats

Yamaha Outboard Gear Case Oil Drain Washer Seal 90430-08020 6HP-300HP 4Boats

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£1.99

Tax included.

YAMAHA GEAR CASE SEAL 90430-08020

Premium Quality Lower Unit Replacement Part

Maintaining your outboard's lower unit is critical for long-term reliability. This premium aftermarket gear case oil drain washer is designed to provide a 100% airtight and watertight seal for your Yamaha outboard's drain and fill plugs. Manufactured from high-grade sealing fiber, it acts as a crush-washer to ensure that gear lubricant stays in and corrosive saltwater stays out.

RELIABILITY: Built to meet or exceed OEM 90430-08020-00 specifications for a perfect, leak-free compression every time.

Key Features

✔ Essential for every gear oil change
✔ High-density fiber construction
✔ Direct fit for 8mm drain screws
✔ Prevents catastrophic gear failure

Technical Specs

Inner Diameter:	8mm (5/16")
Outer Diameter:	13mm (approx.)
Thickness:	1.5mm - 1.9mm
Material:	Hard Compression Fiber
Type:	Single-Use Crush Washer

Compatibility / Fitment Guide

Make/System	Model/Application	Notes
Yamaha Outboard	6HP to 300HP (All Models)	2-Stroke & 4-Stroke
Yamaha WaveRunner	Most models 1984 - Current	Includes FX, SJ, XL models
Parsun / Selva	Most Yamaha-based units	Verify against 8mm screw

OEM Cross Reference

Yamaha OEM	90430-08020-00, 90430-08003, 90430-08021, 90430-08801
Yamaha Alternate	604-45342-00-00, 90430-08020-0
Sierra Marine	18-4698

Questions & Answers

Is this a genuine original part?

This is a premium quality aftermarket replacement part from 4Boats, manufactured to meet or exceed original equipment (OE) standards for fitment and performance.

How do I know if it is compatible?

We recommend checking the SKU 90430-08020. This washer fits virtually all Yamaha outboards from 6HP up to 300HP. If your outboard uses an 8mm drain screw, this is the correct seal.

How many washers do I need for a service?

Standard Yamaha lower unit services require two washers: one for the lower drain plug and one for the upper vent/fill plug. We recommend replacing both at every oil change.

Note: Please verify your original part number against the references above before purchasing. This product is sold by 4Boats / Aftermarket.

For the products under £150 the shipping is £6.99.

Free delivery for most items over £150.

Why choose us

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Every order is checked by the 4Boats team. Contact us before ordering if you need help with part numbers, compatibility or availability.

Yamaha Outboard Gear Case Oil Drain Washer Seal 90430-08020 6HP-300HP 4Boats