Sierra 18-3044 Neoprene Water Pump Impeller, Replaces OMC 385072, for Johnson/Evinrude 85-115 HP Outboards

The Sierra 18-3044 is a neoprene water pump impeller built as a direct replacement for the factory impeller in select Johnson/Evinrude outboard motors. The impeller is the wear component inside the outboard's water pump housing that circulates raw water through the powerhead to keep the engine cool, and a cracked, glazed, or worn-down impeller is one of the most common causes of overheating in outboard motors. This impeller features a 6-fin neoprene design in white, engineered to match OEM dimensions and rotation so it seats correctly in the original water pump housing.

Sierra manufactures this part to meet or exceed the specification of the original equipment part it replaces, and each package includes one impeller. It is sold as an individual wear part, so buyers doing a full water pump service should also plan to replace the housing gasket and wear plate as part of the same job if those show wear.

The 18-3044 is built for Johnson/Evinrude outboards rated at 85 HP (1969-1972), 100 HP (1969-1972), and 115 HP (1969-1970). Confirm your outboard's horsepower and model year against this fitment before ordering, since Sierra offers different impeller part numbers for other year ranges on the same horsepower engines.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3044
• Material: Neoprene
• Color: White
• Number of Fins: 6
• Weight: 0.41 pounds
• Unit Count: 1 impeller per package
• OEM Cross Reference: Mallory 9-45220, GLM 89612, OMC 385072

Fitment

• Johnson/Evinrude outboard, 85 HP, 1969-1972
• Johnson/Evinrude outboard, 100 HP, 1969-1972
• Johnson/Evinrude outboard, 115 HP, 1969-1970

Replaces (OEM)

• Mallory 9-45220
• GLM 89612
• OMC 385072

Frequently Asked Questions

What outboards does the Sierra 18-3044 impeller fit? The Sierra 18-3044 fits Johnson/Evinrude outboards rated at 85 HP for model years 1969-1972, 100 HP for model years 1969-1972, and 115 HP for model years 1969-1970.

Is the 18-3044 a genuine Sierra part or an aftermarket copy? It is a genuine Sierra-manufactured impeller, built as a replacement for the original equipment part and produced to meet or exceed the OEM specification it replaces.

What OEM part numbers does the 18-3044 cross-reference to? The 18-3044 is interchangeable with Mallory 9-45220, GLM 89612, and OMC 385072, so any of those numbers can be used to identify the same impeller.

What material is the impeller made from? The Sierra 18-3044 is molded from neoprene, a synthetic rubber chosen for its resistance to heat and wear inside the outboard's raw water pump.

How many fins does the 18-3044 impeller have? This impeller has a 6-fin design, matching the original configuration used in the Johnson/Evinrude water pump housings it fits.

How many impellers come in one package? Each Sierra 18-3044 package contains one impeller.

How much does the 18-3044 impeller weigh? The Sierra 18-3044 weighs 0.41 pounds.

What causes an outboard water pump impeller to need replacement? Impellers like the 18-3044 wear down or crack over time from heat and friction inside the water pump housing, which reduces raw water flow and can lead to engine overheating.

Does the 18-3044 include the water pump housing or gasket? No, the Sierra 18-3044 is the impeller only; the housing and gasket are separate parts and should be inspected or replaced separately during a water pump service.

Will the 18-3044 fit a Johnson/Evinrude 85 HP from the 1980s? No, the Sierra 18-3044 is specified for the 85 HP Johnson/Evinrude covering 1969-1972; later 85 HP model years use a different Sierra impeller part number.

Is color or fin count a functional spec or just cosmetic? Fin count is functional on the 18-3044, since its 6-fin design is engineered to match the pump housing's flow requirements; the white color of the neoprene is not a performance factor.