Water Pump Gasket - Vespa GTS 250/300

Premium Right Crankcase Water Pump Gasket

Don’t let a weeping coolant leak risk an expensive engine overheat. This premium aftermarket right-side crankcase cover gasket—commonly referred to as the water pump casing gasket—seals the critical mating surface where your water pump assembly integrates into the engine block. Engineered to replace brittle or blown factory seals, it locks fluid passages down tight to keep your engine oil and engine coolant safely separated.

Key Features

• Prevents Fluid Mixing: Creates a high-pressure barrier that stops coolant from bleeding across internal passages into your engine’s oil supply.

• Excellent Thermal Resilience: Formulated from specialized aramid-fiber gasket material that won’t shrink, crack, or degrade under extreme cooling system cycling.

• Precision Die-Cut Alignment: Stamped with absolute precision to line up perfectly with every alignment dowel and bolt hole on the right engine casing.

• Direct OEM Interchange: Matches the dimensional profile and sealing thickness of original factory part number 840504 exactly.

Fitment Guide

Technical Specs

• Manufacturer Part Reference: High-Quality Aftermarket / Replaces OEM 840504, 484793

• Component Type: Right Crankcase Cover / Water Pump Housing Gasket

• Material Composition: High-density, oil-and-coolant resistant aramid fiber compound

• Thickness: Factory-matched standard clearance thickness

• Package Contents: (1) Replacement Crankcase Cover Gasket

Maintenance Note: If you notice a milky, latte-like substance underneath your oil filler cap, or if your coolant levels are dropping mysteriously without a puddle on the floor, your right case gasket or internal mechanical water pump seal has failed. Continued riding with water-contaminated oil will rapidly destroy your engine’s crankshaft bearings.

Installation Tip: Thoroughly clean the old aluminum casing surfaces before installing the new gasket. Use a plastic scraper and brake cleaner to remove any baked-on factory paper or sealant residue—never use a metal razor blade, as even a tiny gouge in the soft aluminum will create a permanent leak path.

Pro Tip: While this paper gasket seals the outer cover plate, it does not stop leaks originating from the spinning water pump impeller shaft itself. If you are going through the effort of tearing down the right engine cover, it is highly recommended to inspect and replace the internal mechanical oil/water seals at the same time to avoid doing the job twice.

WARNING: California Proposition 65