Yamaha - Fuel Pump Diaphragm - Fuel Delivery Component - 63V-24411-00-00

Overview

The diaphragm is one of those parts you don’t see, but you’ll definitely feel when it starts to fail. I’ve worked on motors that wouldn’t stay running or lost power under load, and it traced back to a weak diaphragm not moving fuel like it should. It’s what keeps fuel flowing consistently from the pump to the engine. When it’s fresh, everything runs smoother and more reliable without starving for fuel.

Key Features

• Fuel Pump Operation Control – Flexes to move fuel efficiently through the system.
• OEM Fitment – Built to Yamaha specifications for proper function and installation.
• Consistent Fuel Delivery – Helps maintain steady engine performance under varying conditions.
• Flexible Durable Material – Designed to withstand constant movement and fuel exposure.

Engine & Boat Compatibility

Fits Yamaha outboard engines equipped with diaphragm-style fuel pump systems. Commonly used on small- to mid-range horsepower outboards across fishing boats, tenders, and recreational vessels.

FAQ

Q: What are signs of a failing diaphragm?
A: Engine hesitation, fuel starvation, or difficulty staying running are common signs.

Q: Can a bad diaphragm cause loss of power?
A: Yes, it can restrict fuel flow and reduce engine performance, especially under load.

Q: Should I replace this during fuel pump service?
A: Yes, it’s a key wear item and should be replaced during a rebuild.

Q: Does ethanol fuel affect the diaphragm?
A: Over time, ethanol can cause the material to stiffen or degrade.

Q: Is installation difficult?
A: It’s straightforward during a fuel pump rebuild, just make sure it’s installed correctly and sealed.