Sierra 18-3392 Water Pump Kit with Housing, Evinrude/Johnson 140-150 HP Outboards, Replaces OMC 434421

The Sierra 18-3392 Water Pump Kit with Housing is a complete cooling-system rebuild kit for Evinrude/Johnson outboard motors, supplying the impeller, plate, cup, repair kit components, and the pump housing in one assembly so the entire water pump section can be replaced as a unit rather than sourced piece by piece. The kit is built to meet or exceed the quality of the original equipment part it replaces, restoring reliable raw-water flow to the powerhead and preventing the overheating that results from a worn or cracked impeller and housing. Housed components include a stainless steel and rubber impeller assembly designed for a consistent seal and long service life in the outboard's lower unit. Because the kit includes the housing itself (not just the wear parts), it is well suited for rebuilds where the original housing is worn, cracked, or scored, in addition to routine impeller maintenance. This kit is designated for Evinrude/Johnson outboards rated 140 HP and 150 HP across the fitment ranges listed below; always confirm your engine's horsepower and model year against the fitment table before ordering, since water pump kits are not interchangeable across all outboard years and horsepower ratings.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-3392
• Type: Water Pump Kit with Housing
• Material: Stainless Steel, Rubber
• Weight: 1.68 pounds
• Compatible Horsepower: 140 HP, 150 HP
• Included Components: Main component only
• Warranty: 90 days
• OEM Cross Reference: GLM 12102, Evinrude/Johnson 434421, 5001594, 390768, 392750, 395062, Mallory 9-48203

Fitment

• Evinrude/Johnson 140 HP, 1979 & Up
• Evinrude/Johnson 150 HP, 1979 & Up
• Evinrude/Johnson 150 HP, 20 inch shaft, 1993 & Up

Replaces (OEM)

• GLM 12102
• Evinrude/Johnson 434421
• 5001594
• 390768
• 392750
• 395062
• Mallory 9-48203

Frequently Asked Questions

What outboards does the Sierra 18-3392 water pump kit fit? The Sierra 18-3392 fits Evinrude/Johnson outboards rated 140 HP (1979 and up) and 150 HP (1979 and up, and 150 HP 20 inch shaft models from 1993 and up). Confirm your engine's horsepower, shaft length, and model year before ordering.

Does this kit include the pump housing or just the impeller? Yes, part number 18-3392 is a complete water pump kit that includes the housing, not just the impeller or wear parts, so the full water pump assembly can be replaced at once.

What OEM part numbers does the 18-3392 replace? It is interchangeable with GLM 12102, Evinrude/Johnson 434421, 5001594, 390768, 392750, and 395062, as well as Mallory 9-48203.

How much does the water pump kit weigh? The Sierra 18-3392 water pump kit weighs 1.68 pounds.

What material is the impeller made from? The impeller and related components in the 18-3392 kit are made of stainless steel and rubber.

Is the Sierra 18-3392 equivalent to genuine OMC parts? It is built to meet or exceed the quality of the original equipment part it replaces and is a direct cross-reference to OMC 434421 and the other listed OEM numbers.

What is included in the box with the 18-3392 kit? The kit ships as the main water pump component only; the listed included components consist of the pump kit with housing assembly.

Is a warranty included with this water pump kit? Yes, the Sierra 18-3392 carries a 90 day manufacturer warranty.

Will the 18-3392 work on a 150 HP outboard with a 20 inch shaft? Yes, for 150 HP Evinrude/Johnson outboards with a 20 inch shaft, the 18-3392 kit applies to model years 1993 and up.

Can I use this kit for a routine impeller replacement or is it only for a full rebuild? Since 18-3392 includes the full pump housing along with the impeller and internal components, it can be used for both routine impeller service and a full water pump housing rebuild.