6S5-12121-00-00 Exhaust Valve for Yamaha 252 FSH Sport 1800 2021-2023

Exhaust Valve for Yamaha

This exhaust valve, reference 6S5-12121-00-00, controls exhaust gas flow in the cylinder head of Yamaha 1800 marine engines.

Overview

This exhaust valve for Yamaha fits 252 FSH Sport 1800 models from 2021 to 2023 and replaces a worn or burnt valve in the engine's exhaust path. Made to original dimensions, this exhaust valve for Yamaha seals against the seat to maintain compression and steady running. It suits boat owners and marine techs doing top-end service.

Built For Performance

• Precision-ground valve face for reliable seating
• Heat-resistant alloy built for marine exhaust temperatures
• Stem sizing matched to 6S5-12121-00-00 specifications
• Supports consistent compression and combustion
• Direct-fit replacement for the listed Yamaha engine family

Fits These Machines

• for Yamaha 252 FSH Sport 1800, 2021-2023

On-The-Job Use

• Top-end rebuilds and valve replacement service
• Restoring compression on high-hour marine engines
• Pre-season maintenance checks
• Shop repair work on Yamaha jet boat powerplants

Specs At A Glance

Good To Know

Q: Is this an original Yamaha part? A: No, this is an aftermarket exhaust valve made to fit Yamaha engines and cross-references the 6S5-12121-00-00 number. Confirm your engine code before ordering.

Q: Should exhaust valves be replaced as a set? A: Exhaust valves are often serviced as a set during a top-end rebuild. Inspect valve guides and seats at the same time for the best result.

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