Continental 63003 Engine Coolant Bypass Hose

Continental 63003 Engine Coolant Bypass Hose

Continental 63003 is a molded engine coolant bypass hose built for coolant routing between the heater core, bypass circuits, radiator, and related engine components. Its 0.620-inch inside diameter at both ends and 13.310-inch length support direct replacement applications where a formed hose profile is required.

For Nissan Pathfinder, Nissan Pickup, INFINITI QX4, and select Isuzu and Chevrolet applications, this hose is specified for coolant transfer paths that need a molded fit and resistance to electrochemical degradation. Continental Molded hoses are built around application-specific routing needs, and this part number 63003 follows that approach for service replacement work.

Key Features

• Molded engine coolant bypass hose for coolant circulation paths
• 0.620 in. inside diameter at both ends
• 13.310 in. overall length
• Built to SAE 20R3EC Class D1 and D2 specifications
• Resistant to electrochemical degradation (ECR)
• Continental Molded line replacement for formed hose routing

Detailed Description

Continental 63003 is an engine coolant bypass hose used in heater and bypass circuits where a molded hose shape is required to follow factory routing. It transfers glycol-based coolant to and from the heater core, through bypass passages, and between other cooling-system components. The hose’s molded construction, 0.620-inch end diameters, and 13.310-inch length make it a direct-fit style replacement for listed applications. This part cross-references Gates 21257 for the same application.

Compatible vehicle applications include 1997-2000 INFINITI QX4, 1995 Nissan Pathfinder, and 1995 Nissan Pickup, along with select Isuzu Rodeo, Isuzu Amigo, Isuzu Pickup, Isuzu Trooper, Chevrolet Cavalier, Chevrolet Corsica, Buick Century, Chevrolet Celebrity, Oldsmobile Omega, Oldsmobile Cutlass Ciera, Oldsmobile Firenza, and Mitsubishi Mighty Max listings. Part number 63003 is also referenced in coolant hose searches for molded heater hose and bypass hose replacement.

Common Uses

• Replacing a cracked or leaking heater-to-pipe coolant hose
• Restoring coolant flow through bypass or heater inlet circuits
• Addressing coolant seepage at molded hose bends
• Correcting hose fitment issues on formed cooling-system routes
• Servicing vehicles with electrochemical hose degradation concerns

Installation Notes

• Verify hose routing, end diameter, and overall length before installation.
• Some listed applications note cut-to-fit use or a connector requirement; confirm the vehicle-specific configuration before ordering.
• Check clamps, pipe ends, and adjacent cooling-system components for wear or corrosion during replacement.
• Use the vehicle’s cooling-system service procedure when refilling and bleeding coolant.

Quality Assurance

Continental Molded hoses are engineered to meet SAE 20R3EC Class D1 and D2 requirements and to resist electrochemical degradation in coolant service. Part number 63003 is built for application-specific cooling-system routing and replacement use.