Sierra Molded Hose 18-70948 - Cooler to Thermostat Housing for MerCruiser 454 Mag MPI, 7.4LX MPI Bravo, 502 Mag MPI (Gen VI)

This Sierra molded hose, part number 18-70948, is a direct-fit cooling system hose engineered to connect the cooler to the thermostat housing on applicable MerCruiser inboard/sterndrive engines. It is molded (not a cut-to-length universal hose) so it follows the exact routing path required for a clean, factory-style installation without kinking or restricting coolant flow. The hose is finished in white and is built to Sierra's quality standard, which the company states meets or exceeds the original equipment part it replaces.

It is designed for use on the 454 Mag MPI (Gen VI), 7.4LX MPI Bravo (Gen VI), and 502 Mag MPI (Gen VI) engine platforms, and it replaces OEM number 32-807407. Sierra supplies OEM engine manufacturers and boat builders with cooling system components daily, so this hose is manufactured to hold up to sustained heat cycling and the harsh marine operating environment. Replacing a cracked, softened, or leaking cooler-to-thermostat-housing hose with this molded part restores proper coolant circulation and helps prevent overheating.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-70948
• Product Name: Molded Hose
• Application: Cooler to thermostat housing
• Color: White
• Weight: 0.92 pounds
• UPC: 808282265625
• Replaces (OEM): 32-807407

Fitment

• 454 Mag MPI (Gen VI) (1996-01)
• 7.4LX MPI Bravo (Gen VI) (1996-97)
• 502 Mag MPI (Gen VI) (1996-01)

Replaces (OEM)

• 32-807407

Frequently Asked Questions

What does the Sierra 18-70948 molded hose connect? The Sierra 18-70948 molded hose runs from the cooler to the thermostat housing on the applicable MerCruiser engine.

Which engines is part number 18-70948 designed for? It fits the 454 Mag MPI (Gen VI) (1996-01), the 7.4LX MPI Bravo (Gen VI) (1996-97), and the 502 Mag MPI (Gen VI) (1996-01) engine platforms.

What OEM part number does 18-70948 replace? Sierra 18-70948 replaces OEM number 32-807407.

Is this a molded hose or a universal cut-to-length hose? 18-70948 is a molded hose, shaped to the specific cooler-to-thermostat-housing routing rather than a straight length that needs to be bent or clamped into place.

What color is the Sierra 18-70948 hose? The hose is white.

How much does the 18-70948 hose weigh? It weighs 0.92 pounds.

Will this fit engines outside the listed MerCruiser models? 18-70948 is specified for the 454 Mag MPI (Gen VI), 7.4LX MPI Bravo (Gen VI), and 502 Mag MPI (Gen VI); confirm your engine matches one of these before ordering.

Is Sierra 18-70948 a genuine aftermarket replacement? Yes, it is a Sierra-manufactured replacement part built to meet or exceed the OEM 32-807407 hose it replaces.

What signs indicate the cooler-to-thermostat-housing hose needs replacement? Cracking, softening, or coolant leaks at the fittings on the original hose are signs it should be replaced with a part like the 18-70948.

What is included when I order this part? You receive one Sierra 18-70948 molded hose for the cooler-to-thermostat-housing connection.

What is the UPC for the Sierra 18-70948 hose? The UPC for this part is 808282265625.