Hose Head To Thermostat (N45 N45N N42 N46) (BMW 1 Series E81/E87 / 3 Series E46 / E90 / X3 E83) is a mechanical component designed to connect the thermostat housing to the coolant hose system in selected BMW models. This hose head plays a crucial role in routing coolant through the thermostat to regulate engine temperature effectively. Proper functioning of this part supports engine thermal management, helping to maintain optimal performance and prevent overheating.
This listing suits several BMW engine types including the N45, N45N, N42, and N46. It is compatible with various popular BMW models, such as the 1 Series E81 and E87, 3 Series E46 and E90, and the X3 E83. Buyers should compare this component closely with their existing hose head, especially noting the fit to the thermostat and hose diameter to ensure compatibility with their specific engine and model.
When sourcing this part, verify the engine code and vehicle model to match it correctly to your cooling system layout. The hose head interfaces directly between the thermostat and the head coolant passage and requires precise alignment to avoid leaks or cooling inefficiencies.
- Fitment for BMW engine models N45, N45N, N42, N46
- BMW 1 Series E81/E87, 3 Series E46/E90, X3 E83 coverage
- Critical for coolant flow management through the thermostat housing
If this repair may need matching clips, brackets, lights, panels or more than one part, check more Thermostat, Quick Repair Bundle or Request a Part before ordering.





