The Johnson Pump 09-810B-1 is an original equipment (OEM) service kit for Johnson F4B raw water pumps. Regular impeller replacement is an essential part of marine engine maintenance, helping to maintain efficient seawater circulation and reduce the risk of engine overheating.

Designed to OEM specifications, this kit contains the components required for a straightforward impeller replacement during scheduled servicing.

Kit Contents

• Genuine Johnson Pump MC97 flexible rubber impeller
• Pump cover gasket(s)
• O-ring
• Installation lubricant

Specifications

• Manufacturer: Johnson Pump
• Part Number: 09-810B-1
• Pump Model: F4B
• Impeller Material: MC97 rubber compound
• Outside Diameter: 50.8 mm (2″)
• Width: 22 mm
• Shaft Diameter: 12 mm
• Number of Blades: 6
• Drive Type: Slotted hub

Features

• Genuine OEM Johnson Pump replacement kit
• Designed for Johnson F4B raw water pumps
• Maintains efficient engine cooling performance
• Includes seals and lubricant for convenient servicing
• Ideal for routine maintenance and preventative replacement

Compatibility

Designed for Johnson Pump F4B raw water pumps.

Many marine diesel engines use the F4B pump, but compatibility depends on the specific pump fitted rather than the engine model. Always verify your existing impeller part number or pump model before ordering.

This impeller is commonly fitted to Johnson Pump F35 series raw water pumps and is also used as a replacement in many equivalent pump applications across a range of marine engines and generator sets. Regular replacement helps maintain correct cooling water flow and reduces the risk of overheating caused by worn or damaged impeller vanes.

As impeller specifications can vary by pump model rather than engine brand alone, it is important to confirm compatibility using the pump reference, existing impeller code or dimensions before installation.

Compatibility & Applications

• Designed for Johnson Pump F35 series raw water pumps

• Replaces equivalent impellers such as Jabsco 22405-0001

• Commonly found on marine engines and generators including (but not limited to):

  • Volvo Penta installations using compatible Johnson/Jabsco pumps

  • Westerbeke engines with F35-type raw water pumps

  • Onan and other marine generator sets using equivalent pump specifications

Always verify your pump model or existing impeller reference before ordering.

Key Features

• Genuine replacement impeller 09-808B-1

• Maintains correct raw water flow

• Essential for engine and generator cooling

• Flexible rubber construction

• Suitable for marine cooling systems