F5 Impeller Kit | Johnson Pump 09-1027B-10

Johnson Pump F5 Impeller Kit | 09-1027B-10 | MC97 | Spline Drive | Replaces Volvo Penta 21951348

The Johnson Pump #09-1027B-10 is the replacement impeller kit for the Johnson Pump F5 raw water pump — a pulley-driven, pedestal-mount pump used in marine inboard and sterndrive applications. The F5 uses a spline drive hub (not a keyed shaft), which is a critical distinction when ordering a replacement impeller. Kit includes the impeller, gaskets/O-rings, and a glycerin lubricant packet. The impeller is manufactured from MC97 elastomer, Johnson Pump's proprietary compound for superior fatigue resistance and self-priming capability. Replaces Volvo Penta 21951348 and supersedes Johnson Pump 09-1027B-1.

Part Details:

• Part Number: 09-1027B-10 (Johnson Pump)
• SKU: JP-09-1027B-10
• Manufacturer: Johnson Pump
• Type: F5 Raw Water Pump Impeller Kit
• Drive Type: Spline drive hub (not keyed — confirm before ordering)
• Blades: 12
• Diameter: 2-1/4 in. (57.2 mm)
• Width: 1.24 in. (31.5 mm)
• Material: MC97 elastomer (Johnson Pump proprietary compound)
• Kit Includes: Impeller, gaskets, O-rings, glycerin lubricant packet
• Replaces Volvo Penta: 21951348
• Supersedes Johnson Pump: 09-1027B-1
• Pump Type: F5 — pulley-driven, pedestal-style mount
• Condition: New

Additional Information

Spline Drive vs. Keyed Drive — Critical Distinction:

The Johnson Pump F5 uses a spline drive hub, where the impeller bore has internal splines that engage matching splines on the pump shaft. This is different from a keyed shaft drive, where the impeller has a single keyway slot that engages a drive key on the shaft. The 09-1027B-10 is specifically the spline-drive impeller for the F5 — a keyed impeller will not engage the F5's splined shaft and cannot be substituted. Always confirm your pump's drive type before ordering a replacement impeller.

About the Johnson Pump F5:

The F5 is a pedestal-mount raw water pump with a pulley drive, meaning it is belt-driven from the engine rather than directly coupled to the engine's raw water pump drive shaft. Pedestal-mount pumps are common on larger diesel inboards and some gasoline inboard applications where the engine does not have an integral raw water pump. The F5's pulley drive means impeller service requires belt removal in addition to pump cover removal — plan for additional disassembly time compared to a direct-drive pump service.

MC97 Elastomer:

MC97 is Johnson Pump's proprietary elastomer compound engineered for marine raw water impeller service. It provides superior hub bonding, blade flexibility across temperature ranges, and fatigue resistance compared to standard neoprene impellers. For a detailed explanation of MC97's properties, see the Johnson Pump JP-09-707B-1 (15000K) impeller kit.

For other Johnson Pump F-series impeller kits, also see:

• Johnson Pump JP-09-707B-1 (15000K) — MC97, keyed shaft, fits Cummins 4B/6B/QSD and MerCruiser 7.3L/4.2L QSD diesel
• Johnson Pump 09-821BT-1 (F75) — M97, fits Hino, M.A.N., Volvo Penta, Yanmar F75 raw water pumps

Frequently Asked Questions

1. How do I confirm this impeller fits my Johnson Pump F5?
Confirm your pump model is the Johnson Pump F5 — check the pump body or nameplate for the model designation. Verify the drive type is spline (not keyed) before ordering. If your pump application is a Volvo Penta engine, cross-reference against Volvo Penta 21951348 to confirm applicability. Contact us at MacombMarineParts.com with your pump model or engine model and serial number if you need fitment confirmation.

2. What is the difference between 09-1027B-1 and 09-1027B-10?
The 09-1027B-10 is the current production part number that supersedes 09-1027B-1. They are successive revisions of the same F5 impeller kit. If your parts reference shows 09-1027B-1, order the 09-1027B-10.

3. Does this kit include all the sealing components for a complete pump cover service?
Yes — the 09-1027B-10 kit includes gaskets, O-rings, and glycerin lubricant in addition to the impeller. Replace all included sealing components at each service — do not reuse the old gasket or O-rings when reinstalling the pump cover.

4. What lubricant should I use to install the impeller?
Use the glycerin lubricant packet included in the kit. Glycerin is the correct lubricant for flexible impeller installation — it lubricates the impeller for installation without degrading the elastomer. Do not use petroleum-based lubricants or silicone grease, which can cause MC97 elastomer swelling. Install with vanes bent in the correct rotational direction per the pump's service instructions.