Radiator Hose Filler 1.5in Hose To 1.25in Hos

The MOROSO Radiator Hose Filler 1.5in Hose to 1.25in Hose (MPN 63740) is an aluminum filler neck designed to bridge cooling system hose size transitions in custom and high-performance cooling applications. This adapter simplifies radiator installation when upgrading or modifying engine cooling systems with mismatched hose diameters, eliminating the need for improvised solutions or additional plumbing components.

Constructed from aluminum in natural finish, this hose mount filler neck accommodates 1.5-inch inlet hose while reducing to a 1.25-inch outlet connection. The direct hose-mount design allows secure attachment to both radiator and cooling line without requiring additional fittings. Aluminum construction provides corrosion resistance and durability in engine bay environments while maintaining a lightweight profile suitable for racing and street applications. The adapter's compact dimensions (3.4 x 3.4 x 5.7 inches) fit tight engine compartments.

This filler neck adapter is ideal for hot rod builders, custom car enthusiasts, and performance engine builders who are fabricating unique cooling systems or integrating components with non-standard hose sizing. MOROSO specializes in cooling system components and performance plumbing solutions, making this adapter a reliable choice for applications requiring precision hose transitions. Engine bay temperatures and coolant pressure demand proper fittings—this adapter ensures a direct, leak-resistant connection between differently sized hose runs.

Whether upgrading a classic engine's cooling system or fabricating a modern performance build, having the correct hose transition component prevents coolant leaks and system inefficiency. The MOROSO 63740 integrates into custom radiator setups where off-the-shelf solutions don't match available hose diameters, making it an essential adapter for serious cooling system work.