# 6H1-43861-10 Yamaha O-Ring | Genuine OEM Yamaha Outboard Part

🔧 Product Description

  

Genuine Yamaha Trim Cylinder End-Cap O-Ring - Part Number: 6H1-43861-10

  

A genuine Yamaha hydraulic O-ring fitted around the trim-cylinder end screw on selected power trim and tilt assemblies.

  

The O-ring seals the threaded end cap against the trim-cylinder bore, retaining hydraulic pressure and preventing water from entering around the end-cap joint.

  

⚙️ Key Features

  

• Genuine Yamaha OEM trim-cylinder O-ring

• Correct Yamaha part number 6H1-43861-10

• Seals the trim-cylinder end screw to the cylinder body

• Used with trim dust seal 6H1-43822-10

• Included in replacement trim-cylinder end-cap kits

  

🔄 Supersession & Cross Reference

  

OEM Supersession Chain:

  

• 6H1-43861-10 → Later service reference for 6H1-43861-00

• 6H1-43861-00 earlier Yamaha trim-cylinder O-ring reference

  

OEM / Related Numbers:

  

• 6H1-43861-10

• 6H1-43861-10-00

• 6H1438611000

• 6H1-43861-00

• 6H1-43821-11 related trim-cylinder end screw

• 6H1-43822-10 related trim-dust seal

• 6H1-43875-00 related retaining ring

  

Aftermarket / Verified Equivalents:

  

• Direct aftermarket O-ring: 6H1-43861-10

• Included in aftermarket 6H1-43821-11 end-cap assemblies

• Included in specialist Yamaha trim-cylinder seal kits

  

🚤 Compatibility

  

Commonly used on:

  

• Yamaha twin trim-cylinder hydraulic assemblies

  

Typically suits:

  

• Engine models:

• Yamaha 40HP and 50HP trim systems using the 6H1 end cap

• Yamaha 55HP

• Yamaha 60HP and 60F

• Yamaha 70HP and 70B

• Yamaha 75HP and C75

• Yamaha 80HP

• Yamaha 85HP and C85

• Yamaha 90HP and 90A

• Yamaha 60FET 2000

• Yamaha 60FETO 2016

• Yamaha 90AETO 2009

  

• HP Range: Commonly 40HP - 90HP

• Engine Type: Yamaha two-stroke and selected four-stroke power trim

• Year Range: Approximately 1990s - 2010s, dependent on trim unit

  

🔌 Function

  

The O-ring seals the trim-cylinder end cap so hydraulic pressure is retained around the moving trim piston.

  

Common signs of failure:

  

• Hydraulic oil leaks around the end-cap threads

• Engine slowly lowers after trimming

• Trim response becomes weak or uneven

• O-ring becomes flattened, cut or swollen

• Water or corrosion is found behind the end cap

  

📦 Condition

  

• Genuine Yamaha part

• Brand new

• Supplied in original or equivalent packaging

## Details

- **Price:** 5.0 AUD
- **Vendor:** Yamaha
- **Tags:** Yamaha Marine Parts | Outboard Engine Parts & Components

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 5.00 AUD | In stock |

## Images

- 6H1-43861-10 Yamaha O-Ring | Genuine OEM Yamaha Outboard Part

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> Source: [Sawley's Auto and Marine](https://www.sawleysautoandmarine.com.au/products/6h1-43861-10-o-ring)
> Updated: 2026-07-11