6S5-12121-00-00 Exhaust Valve for Yamaha 295XD 1800 2026

Exhaust Valve for Yamaha

This exhaust valve, OEM cross-reference 6S5-12121-00-00, regulates exhaust gas flow from the cylinder head on Yamaha 295XD 1800 marine engines.

Overview

This exhaust valve is a replacement component for the Yamaha 1800 engine fitted to the 295XD. The valve holds compression during combustion and opens to let exhaust gases exit the cylinder on each cycle. It is aimed at boat owners and marine technicians handling top-end work on a Yamaha 1800 powerplant.

Built For Performance

• OEM cross-reference 6S5-12121-00-00 for accurate matching
• Valve dimensions made for the Yamaha 1800 cylinder head
• Heat-resistant alloy built for sustained marine exhaust temperatures
• Ground stem surface for smooth travel through the valve guide
• Faced head for a reliable seal against the valve seat

Fits These Machines

• for Yamaha 295XD (2026)
• for Yamaha 1800 engine applications

On-The-Job Use

• Cylinder head rebuilds on Yamaha 1800 marine engines
• Replacing a burnt or compression-loss exhaust valve
• Valve clearance and compression maintenance
• Marina and boat yard repair work on the 295XD

Specs At A Glance

Good To Know

Q: How many exhaust valves does a Yamaha 1800 engine need? A: The 1800 four-stroke engine uses one exhaust valve per cylinder, so order the quantity your head service requires. Confirm your engine configuration before purchase.

Q: Should exhaust valves be replaced as a set? A: Many mechanics replace all valves in a serviced head at once to keep wear even across cylinders. Follow your service manual for the correct procedure.

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