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Celebrating over 50 years of Trusted Marine Service
Over 50 years of Trusted Marine Service

Sierra 18-3306 Johnson Pump F6 / Jabsco Impeller Repair Kit

Original price $116.89 - Original price $116.89
Original price
$116.89
$116.89 - $116.89
Current price $116.89

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You have 30 days to request a return. All sale items are final sale.

Product Description

The Sierra 18-3306 is a neoprene flexible-impeller repair kit for Johnson Pump F6-series raw-water pumps and equivalent Jabsco marine cooling-pump applications. The impeller measures approximately 2-1/4 inches in diameter by 1-15/16 inches wide and uses a splined brass hub. Sierra lists the kit for a broad range of Indmar-powered inboard boats, including Monsoon, Hammerhead and Ford Raptor engine packages.

Key Features

  • Sierra part number: 18-3306
  • Flexible raw-water pump impeller repair kit
  • Neoprene impeller material
  • Approximately 2-1/4 in. / 57.2 mm diameter
  • Approximately 1-15/16 in. / 49.2 mm width
  • 12 flexible blades
  • Splined brass drive hub
  • Fits Johnson Pump F6-series applications
  • Includes replacement O-ring 18-7123
  • UPC: 030999975690

Pump / Engine Compatibility

Sierra identifies the 18-3306 for:

  • All compatible Johnson Pump F6 pumps
  • Indmar Monsoon 320, 325, 330, 335, 340 and 350 hp
  • Indmar Hammerhead Callaway 365
  • Indmar Hammerhead 380, 383 and 400 hp
  • Indmar carbureted LCR engines
  • Indmar 8.1L engines
  • Indmar Ford Raptor 400, 450 and 575
  • Supra, Moomba, MasterCraft and Tige boats using applicable Indmar engines
  • Challenger 5.7L engines used in compatible Axis wake boats
  • 2022-and-newer Malibu and Axis M5 and M6
  • 2019–2021 M5 and M6 applications converted to the newer pump-housing design

Equivalent impeller references also place this part in compatible Johnson Pump, Jabsco and Yanmar marine cooling systems.

Fitment Notice

Before ordering, confirm all three critical details:

  • The installed pump is a compatible Johnson F6-series or equivalent pump.
  • The shaft uses the correct splined drive.
  • The original impeller number matches one of the supported cross references.

Do not rely on boat brand or engine horsepower alone. Some Malibu and Axis applications changed pump designs, and 2019–2021 engines require confirmation that the pump housing has been converted to the newer configuration.

When This Part Needs Replacement

Replace the impeller when:

  • Cooling-water flow becomes weak or intermittent
  • The engine begins operating hotter than normal
  • The pump struggles to prime
  • Vanes are cracked, torn, hardened or permanently curled
  • Pieces are missing from the old impeller
  • The pump has been operated without water
  • The boat is undergoing scheduled annual cooling-system maintenance

If vanes are missing, inspect downstream hoses, oil coolers, transmission coolers and heat exchangers for trapped fragments before restarting the engine.

Installation Notes

  • Disconnect the battery and close the raw-water intake seacock.
  • Remove the pump cover and note the original impeller orientation.
  • Extract the old impeller without scoring the pump housing.
  • Inspect the cover plate, cam, shaft and pump body for excessive wear.
  • Recover any missing impeller fragments from the cooling system.
  • Lightly lubricate the replacement impeller with glycerine or a suitable water-based impeller lubricant.
  • Align the splined hub carefully with the pump shaft.
  • Install the supplied O-ring and any application-specific gasket required by the pump.
  • Tighten the cover screws evenly.
  • Reopen the seacock before starting the engine.
  • Verify strong water flow and inspect the pump for leaks immediately after startup.

Alternate / Cross-Reference Part Numbers

  • Sierra: 18-3306
  • Johnson Pump: 09-812B
  • Johnson Pump: 09-812B-1
  • Jabsco: 13554-0001
  • Jabsco: 13554-0001-P
  • Yanmar: 119773-42600
  • Yanmar: 119773-42600-00
  • Indmar: S685007
  • Indmar: 685001
  • Yamaha: 6TA-12457-00
  • Mallory Marine: 9-45704
  • O-ring included: Sierra 18-7123
  • UPC: 030999975690

Compatible & Related Parts

Direct cross-reference and related impeller kits for Johnson Pump F6 and Jabsco applications:

Parts Desk Insight

The Sierra 18-3306 is best identified by its 57 mm diameter, approximately 49 mm width and splined hub. It is a common Johnson F6 and Indmar impeller, but similar-looking impellers can have different widths or shaft drives. Matching 09-812B, 13554-0001 or S685007 is the safest fitment check.

Shipping information

In-stock and OEM parts: ship same or next business day.

Locally warehoused items: ship within 3–4 business days.

Special-order items: timeline confirmed after order.

Returns & warranty

Returns & Satisfaction Guarantee

We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.

If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.

To qualify for a return:


  • Item must be in new, unused condition

  • Product must be in its original packaging

  • All parts, components, hardware, manuals, and accessories must be included

  • Packaging must be undamaged and suitable for resale

Important:

Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.

We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.

For return authorization, please contact our support team before shipping anything back.

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