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

🚤 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

🔄 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

📦 Condition

• Genuine Yamaha part
• Brand new
• Supplied in original or equivalent packaging