Dorman 902-5198 Engine Coolant Thermostat Housing

OE Quality 60-Day Returns

Dorman 902-5198 Engine Coolant Thermostat Housing

Brand	Dorman 902-5198
Air Vent (Bleeder Valve)	No
Bolt Hole Center To Bolt Hole Center	1.85
Bolt Hole Center To Bolt Hole Center	1.89
Bolt Hole Center To Bolt Hole Center	1.94
Bolt Hole Center To Bolt Hole Center	2.07
Bolts Included	No
Color	Natural
Flange Thickness	0.41
Gasket Or Seal Included	Yes
Height	2.94
Inlet Port Diameter	1.29
Material	Aluminum
Mounting Hole Diameter	0.27
Mounting Hole Quantity	7
O Rings Included	Yes
Outlet Port Diameter	1.91
Package Contents	1 Gasket; 1 Thermostat Housing; 1 Thermostat
Thermostat Included	No
Fits	Mazda · 60 vehicles

OE-style replacement. Matches stock fit and durability for a straightforward swap.

Aluminum construction. Helps withstand extreme temperature changes for longer service life.

Seal included. Comes with a gasket and O-rings for a tighter, cleaner install.

Cross-references Four Seasons 86029, Motorad CH6129 and PE0115172 for the same application. See all 3.

$66.63Free shipping

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Engine Coolant Thermostat Housing for Mazda

Dorman 902-5198 is a replacement engine coolant thermostat housing built to match the fit and durability of the original housing on specified Mazda vehicles. It is made from aluminum and engineered to handle repeated temperature swings in the cooling system, helping maintain a secure thermostat seal and stable coolant flow.

Key Features

Aluminum housing with a natural finish
Includes gasket and O-rings for sealing surfaces
Seven mounting holes for OE-style attachment points
Inlet port diameter: 1.29 in.; outlet port diameter: 1.91 in.
Flange thickness: 0.41 in.; height: 2.94 in.
Designed for Mazda CX-5, Mazda 3, Mazda 3 Sport, Mazda CX-3, and Mazda 6 cooling system applications
Part number 902-5198 for direct catalog lookup

Detailed Description

This thermostat housing is built for drivers replacing a worn, cracked, or leaking cooling system housing on a Mazda CX-5, Mazda 3, Mazda 3 Sport, Mazda CX-3, or Mazda 6. The aluminum construction supports durability in high-heat engine environments, while the included gasket and O-rings help create a proper seal at the housing interface. Dorman 902-5198 is shaped to match the stock housing dimensions and mounting layout for the listed applications, making it a practical OE-style replacement for cooling system service.

This part cross-references Four Seasons 86029 for the same application.

Fitment

Fits 2013-2019 Mazda CX-5, N/A. Engine coolant thermostat housing for cooling system.
Fits 2012-2018 Mazda 3, N/A. Engine coolant thermostat housing for cooling system.
Fits 2012-2018 Mazda 3 Sport, N/A. Engine coolant thermostat housing for cooling system.
Fits 2016-2018 Mazda CX-3, N/A. Engine coolant thermostat housing for cooling system.
Fits 2014-2017 Mazda 6, N/A. Engine coolant thermostat housing for cooling system.

Common Repair Issues

Coolant leaks at the thermostat housing
Cracked or warped housing from heat cycling
Failed sealing surfaces causing loss of coolant
Overheating concerns related to restricted coolant flow
Service replacement for a damaged Mazda thermostat housing

Installation Notes

Verify the inlet and outlet port sizes, mounting hole count, and housing shape against the original part before installation. Clean the mating surfaces thoroughly, inspect the thermostat and surrounding cooling components, and refill the system with the correct coolant after installation. Bleeding air from the cooling system is important after service, especially when replacing a thermostat housing on Mazda CX-5, Mazda 3, Mazda 3 Sport, Mazda CX-3, or Mazda 6 models.

Quality Assurance

Dorman designs this replacement housing to match the fit and durability of the stock thermostat housing on the listed vehicles and to withstand extreme temperature changes for extended service life.

This part fits 60 vehicles

Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

Year	Make	Model	Transmission	Liters	Cylinders	Fuel Type	Position	Notes
2019	Mazda	CX-5	—	2.0L	L4	GAS	N/A	Engine coolant thermostat housing for cooling system.
2018	Mazda	3	Automatic	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2018	Mazda	3	Manual	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2018	Mazda	3	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2018	Mazda	3	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2018	Mazda	3 Sport	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2018	Mazda	3 Sport	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2018	Mazda	3 Sport	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2018	Mazda	CX-3	—	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2018	Mazda	CX-5	—	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	3	Automatic	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	3	Manual	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	3	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	3	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	3 Sport	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	3 Sport	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	3 Sport	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	6	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	CX-3	—	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	CX-5	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2017	Mazda	CX-5	—	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	3	Automatic	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	3	Manual	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	3	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	3	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	3 Sport	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	3 Sport	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	3 Sport	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	6	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	CX-3	—	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	CX-5	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2016	Mazda	CX-5	—	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	3	Automatic	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	3	Manual	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	3	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	3	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	3 Sport	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	3 Sport	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	3 Sport	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	6	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	CX-5	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2015	Mazda	CX-5	—	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2014	Mazda	3	Automatic	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2014	Mazda	3	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2014	Mazda	3	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2014	Mazda	3 Sport	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2014	Mazda	3 Sport	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2014	Mazda	3 Sport	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2014	Mazda	6	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2014	Mazda	CX-5	—	2.5L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2014	Mazda	CX-5	—	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2013	Mazda	3	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2013	Mazda	3	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2013	Mazda	3 Sport	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2013	Mazda	3 Sport	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2013	Mazda	CX-5	—	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2012	Mazda	3	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2012	Mazda	3	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2012	Mazda	3 Sport	Automatic	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
2012	Mazda	3 Sport	Manual	2.0L	L4	—	N/A	Engine coolant thermostat housing for cooling system.
No rows match your filter.

Directly replaces or cross-references 3 part numbers

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.

Four Seasons — 86029Motorad — CH6129PE0115172