420256606 Valve Seat Sleeve for Sea-Doo Sport 21-300 1630 2026

Valve Seat Sleeve for Sea-Doo

This Valve Seat Sleeve, part number 420256606, is a replacement component that presses into the cylinder head to support and locate the valve seat, helping maintain proper valve sealing on 1630cc engines.

Overview

The Valve Seat Sleeve for Sea-Doo is a precision-fit component made for 1630cc engine cylinder heads. This valve seat sleeve holds the valve seat in correct alignment so valves seal properly under combustion pressure. It is intended for riders and mechanics servicing Sea-Doo Sport 21-300 models.

Built For Performance

• Machined to seat the valve concentrically in the cylinder head
• Heat-resistant material suited to combustion temperatures
• Supports the valve seat area through repeated combustion cycles
• Helps restore valve sealing during a top-end rebuild
• Direct replacement for the original sleeve part number 420256606

Fits These Machines

• for Sea-Doo Sport 21-300 1630, 2026

On-The-Job Use

• Cylinder head service and top-end rebuilds
• Valve seat replacement and repair work
• Restoring compression on high-hour marine engines
• Shop and DIY engine repair

Specs At A Glance

Good To Know

Q: Is this an original Sea-Doo part? A: No, this is an aftermarket valve seat sleeve that cross-references part number 420256606. It is designed to fit the listed Sea-Doo 1630cc models.

Q: How many sleeves do I need? A: This listing is for a single valve seat sleeve, so order the quantity matching the seats you are replacing. Check your engine's valve count before ordering.

Slight variation in finish or dimensions may occur between production runs, and fit can depend on serial number, so confirm compatibility before ordering.