Thermostat Housing and Water Necks

Thermostat housing, water neck, water outlet, coolant housing…they’re all names for the same thing. This component is where the upper radiator hose plugs...

Thermostat housing, water neck, water outlet, coolant housing…they’re all names for the same thing. This component is where the upper radiator hose plugs in, and it also contains your mechanical thermostat. Grab a stock replacement to replace a leaky or broken one, dress up your engine with a chrome or anodized finish, or use a 360° swiveling model for versatility on your custom cooling system.

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Our powerful search tools make it easy to find the right water neck from manufacturers like Meziere, Dorman, Mr. Gasket, Four Seasons, Trans-Dapt, ACDelco, and so many more.

Top Brands

Our powerful search tools make it easy to find the right water neck from manufacturers like Meziere, Dorman, Mr. Gasket, Four Seasons, Trans-Dapt, ACDelco, and so many more.

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Results 1 - 25 of 100

Moroso Manifold Filler Necks 63465

Water Neck, Billet Aluminum, Black Anodized, Radiator Cap Filler, Chevy, Big/Small Block, Each

Part Number: MOR-63465

5.0 out of 5 stars ( 5 )

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Summit Racing™ Water Necks SME-2200

Water Neck, Aluminum, Natural, 90 Degree, Chevy, Big/Small Block, Each

Part Number: SME-2200

4.17 out of 5 stars ( 12 )

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Redhorse Performance 4910 Series Thermostat Housing Assemblies 4910-383-24-5

Water Neck, Aluminum, Clear Anodized, O-Ring, 75 Degree, 1.500 in. Outlet, With Filler Neck for Radiator Cap, Chevy, Small/Big Block, Each

Part Number: HSE-4910-383-245

Not Yet Reviewed

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Moroso Billet Aluminum Filler Necks 63466

Water Neck, Billet Aluminum, Natural, Radiator Cap Filler, Chevy, Big/Small Block, Each

Part Number: MOR-63466

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Moroso Billet Aluminum Filler Necks 63467

Water Neck, Billet Aluminum, Natural, Radiator Cap Extension, 5.75 in. Tall, Chevy, Big/Small Block, Each

Part Number: MOR-63467

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

CVR Intake Manifold Water Filler Necks TSH3CL

Water Neck, Radiator Cap Filler Neck Style, Billet Aluminum, Clear Anodized, Chevy, Each

Part Number: CVS-TSH3CL

Not Yet Reviewed

Estimated Ship Date: May 27, 2026 if ordered today

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Estimated Ship Date: May 27, 2026 if ordered today

Moroso Billet Aluminum Filler Necks 63468

Water Neck, Billet Aluminum, Black, Radiator Cap Filler, Chevy, Big/Small Block, Each

Part Number: MOR-63468

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Apr 15, 2026 if ordered today

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Estimated Ship Date: Apr 15, 2026 if ordered today

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Moroso Manifold Filler Necks 63465

5 out of 5 stars ( 5 )

Estimated Ship Date: Monday 3/23/2026

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Drag Race Solutions Water Filler Necks 3300-005B

Drag Race Solutions Water Filler Necks 3300-005B

Water Filler Neck, Radiator Cap Filler Neck Style, Aluminum, Black Powdercoated, Kit

Part Number: CHH-3300-005B

Not Yet Reviewed

Estimated Ship Date: Mar 30, 2026 if ordered today

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Estimated Ship Date: Mar 30, 2026 if ordered today

Redhorse Performance 4910 Series Thermostat Housing Assemblies 4910-383-20-2

Water Neck, Aluminum, Black Anodized, O-Ring, 75 Degree, 1.250 in. Outlet, With Filler Neck for Radiator Cap, Chevy, Small/Big Block, Each

Part Number: HSE-4910-383-202

Not Yet Reviewed

Estimated Ship Date: Apr 9, 2026 if ordered today

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Estimated Ship Date: Apr 9, 2026 if ordered today

Redhorse Performance 4910 Series Thermostat Housing Assemblies 4910-383-20-3

Water Neck, Aluminum, Red Anodized, O-Ring, 75 Degree, 1.250 in. Outlet, With Filler Neck for Radiator Cap, Chevy, Small/Big Block, Each

Part Number: HSE-4910-383-203

Not Yet Reviewed

Estimated Ship Date: Apr 9, 2026 if ordered today

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Estimated Ship Date: Apr 9, 2026 if ordered today

Redhorse Performance 4910 Series Thermostat Housing Assemblies 4910-383-24-1

Water Neck, Aluminum, Blue Anodized, O-Ring, 75 Degree, 1.500 in. Outlet, With Filler Neck for Radiator Cap, Chevy, Small/Big Block, Each

Part Number: HSE-4910-383-241

Not Yet Reviewed

Estimated Ship Date: Apr 10, 2026 if ordered today

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Estimated Ship Date: Apr 10, 2026 if ordered today

Redhorse Performance 4910 Series Thermostat Housing Assemblies 4910-383-20-5

Water Neck, Aluminum, Clear Anodized, O-Ring, 75 Degree, 1.250 in. Outlet, With Filler Neck for Radiator Cap, Chevy, Small/Big Block, Each

Part Number: HSE-4910-383-205

Not Yet Reviewed

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Redhorse Performance 4910 Series Thermostat Housing Assemblies 4910-383-20-1

Water Neck, Aluminum, Blue Anodized, O-Ring, 75 Degree, 1.250 in. Outlet, With Filler Neck for Radiator Cap, Chevy, Small/Big Block, Each

Part Number: HSE-4910-383-201

Not Yet Reviewed

Estimated Ship Date: Apr 9, 2026 if ordered today

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Estimated Ship Date: Apr 9, 2026 if ordered today

Redhorse Performance 4910 Series Thermostat Housing Assemblies 4910-383-24-3

Water Neck, Aluminum, Red Anodized, O-Ring, 75 Degree, 1.500 in. Outlet, With Filler Neck for Radiator Cap, Chevy, Small/Big Block, Each

Part Number: HSE-4910-383-243

Not Yet Reviewed

Estimated Ship Date: Apr 10, 2026 if ordered today

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Estimated Ship Date: Apr 10, 2026 if ordered today

Canton Racing Billet Aluminum Racer Water Necks with Filler Top 80-006

Water Neck, Aluminum, Black/Natural, 90 Degree, Chevy, Big/Small Block, Kit

Part Number: CTR-80-006

5.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Drag Race Solutions Water Filler Necks 3300-001B

Water Neck, Offset Adapter Style, Billet Aluminum, Black Powdercoated, Chevy, Each

Part Number: CHH-3300-001B

Not Yet Reviewed

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

CSR Intake Manifold Water Filler Necks CSR 970C

Water Neck, Billet Aluminum, Clear Anodized, Straight Up, Chevy, Big/Small Block, Each

Part Number: CSI-970C

4.67 out of 5 stars ( 3 )

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Drag Race Solutions Water Filler Necks 3300-001R

Water Neck, Offset Adapter Style, Billet Aluminum, Natural, Chevy, Each

Part Number: CHH-3300-001R

Not Yet Reviewed

Estimated Ship Date: Apr 3, 2026 if ordered today

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Estimated Ship Date: Apr 3, 2026 if ordered today

URO Parts Thermostat Housings and Coolant Flanges for 2002-2008 COOPER - 11537512733PRM

Engine Coolant Thermostat Housing. 2002-2008 Mini

Part Number: URO-007950

Not Yet Reviewed

Estimated Ship Date: Apr 20, 2026 if ordered today

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Estimated Ship Date: Apr 20, 2026 if ordered today

Drag Race Solutions Water Filler Necks 3300-002B

Water Necks, Water Filler Neck, Straight, Billet Aluminum, Black, Each

Part Number: CHH-3300-002B

Not Yet Reviewed

Estimated Ship Date: Mar 26, 2026 if ordered today

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Estimated Ship Date: Mar 26, 2026 if ordered today

URO Parts Thermostat Housings and Coolant Flanges for 2002-2008 COOPER - 17127515494PRM

Radiator Coolant Hose Connector. 2002-2008 Mini

Part Number: URO-011239

Not Yet Reviewed

Estimated Ship Date: Apr 20, 2026 if ordered today

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Estimated Ship Date: Apr 20, 2026 if ordered today

URO Parts Thermostat Housings and Coolant Flanges for 1984-1993 190E - 1022030374

Coolant Thermostat Housing, Mercedes-Benz, Each

Part Number: URO-008052

Not Yet Reviewed

Estimated Ship Date: Apr 20, 2026 if ordered today

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Estimated Ship Date: Apr 20, 2026 if ordered today

URO Parts Thermostat Housings and Coolant Flanges LR122710

Engine Coolant Outlet Flange. 2014-2017 Land Rover

Part Number: URO-016399

Not Yet Reviewed

Estimated Ship Date: Monday 3/23/2026 if shipped by air

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Estimated Ship Date: Monday 3/23/2026 if shipped by air

Drag Race Solutions Water Filler Necks 3300-005P

Filler Neck Blower Water - Polished

Part Number: CHH-3300-005P

Not Yet Reviewed

Estimated Ship Date: Mar 30, 2026 if ordered today

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Estimated Ship Date: Mar 30, 2026 if ordered today

Drag Race Solutions Water Filler Necks 3300-002R

Water Necks, Water Filler Neck, Straight, Billet Aluminum, Natural, Each

Part Number: CHH-3300-002R

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Mar 23, 2026 if ordered today

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Estimated Ship Date: Mar 23, 2026 if ordered today

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