Sierra Water Pump Gasket 18-2919 - Replaces 27-426311, 27-42631

The Sierra 18-2919 Water Pump Gasket is a replacement gasket engineered to seal the water pump housing on applicable outboard engines, restoring proper compression and preventing leaks at the pump base. It is designed as a direct fit for water pump assemblies that call for OEM 27-426311 or 27-42631 gaskets, giving installers a reliable seal without the delays of sourcing original equipment. Because a worn or torn water pump gasket is a common cause of reduced cooling pressure and pump leakage, replacing this gasket during any water pump service or impeller change helps ensure the housing seats correctly and the cooling system holds pressure as intended. This is a lightweight, single-use sealing component intended to be installed fresh any time the water pump housing is removed or serviced, rather than reused. Keeping a gasket like this on hand alongside an impeller kit is standard practice for a complete water pump rebuild, since reusing an old gasket after the housing has been disturbed increases the risk of a leak path forming at the mating surface. The Sierra 18-2919 is manufactured to the dimensions and material spec needed to match the original gasket it replaces, so it installs in the same location using the same fasteners as the factory part.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-2919
• Product Name: Water Pump Gasket
• Weight: 0.02 pounds
• UPC: 030999314239

Fitment

Fits water pump housings that use the 27-426311 or 27-42631 gasket.

Replaces (OEM)

• 27-426311
• 27-42631

Frequently Asked Questions

What does the Sierra 18-2919 gasket fit? The Sierra 18-2919 is a water pump gasket designed to fit water pump housings that call for OEM gasket 27-426311 or 27-42631.

Is 18-2919 the same as OEM part 27-426311? Yes, the Sierra 18-2919 water pump gasket is a direct replacement for OEM 27-426311, and it also replaces OEM 27-42631.

What is the 18-2919 gasket made for? It is a water pump housing gasket, used to seal the mating surface of an outboard water pump during installation or service.

How much does the 18-2919 water pump gasket weigh? The Sierra 18-2919 weighs 0.02 pounds.

Should I replace the water pump gasket every time I service the pump? Yes, a water pump gasket such as the Sierra 18-2919 is a single-use sealing part and should be replaced any time the water pump housing is removed, rather than reinstalling the old gasket.

Does the 18-2919 gasket come with the impeller? No, the Sierra 18-2919 is sold as a standalone gasket and does not include an impeller or other water pump kit components.

Is the Sierra 18-2919 gasket genuine Sierra or aftermarket? The 18-2919 is a Sierra-branded gasket manufactured as a replacement part carrying the Sierra part number 18-2919.

What OEM numbers cross-reference to the Sierra 18-2919? The Sierra 18-2919 water pump gasket cross-references to OEM numbers 27-426311 and 27-42631.

Can I reuse my old water pump gasket instead of buying the 18-2919? Reusing an old water pump gasket after the housing has been disturbed increases the risk of a leak, so replacing it with a fresh gasket like the Sierra 18-2919 during service is recommended.

What is the UPC for the Sierra 18-2919 gasket? The UPC for the Sierra 18-2919 water pump gasket is 030999314239.