2021 Honda Clarity Cooling System Parts

This table covers the engine coolants and antifreeze formulations specified for this cooling system. Typical signs include a rising temperature gauge, rusty or sludged coolant, or a heater that blows cold. Use the chemistry named in the notes. Mixing silicate, OAT and HOAT formulas can gel in the radiator. Read more

17 Coolant / Antifreeze parts are listed for the 2021 Honda Clarity, from PRESTONE, PEAK, VALVOLINE and 4 other brands. FVP MV5050GAL carries the "Popular" badge. 9 parts fit every engine; the other 8 are engine-specific.

The Compatible With All Colors section lists 1 option from PRESTONE — grouped under the catalog's "Compatible With All Colors" designation — the notes column spells out what sets them apart. PRESTONE AF3055 is listed in this group.

In the Economy grade, FVP, PRESTONE, PEAK and 1 other brand supply 4 parts: the catalog's value-priced group. A representative part number is FVP MV5050GAL.

The Premium section lists 5 options from PRESTONE and PEAK — a step above OE specification in materials, tolerances or warranty terms. PRESTONE AF2100 is listed in this group.

The Standard Replacement section lists 7 options from VALVOLINE, BECK/ARNLEY, AISIN and 2 other brands — built to original-equipment specification. VALVOLINE 861398 is listed in this group.

This table covers the caps on the overflow / expansion tank. Typical signs include a leak at the neck, a cap that will not hold pressure, or a missing tether. Match the pressure rating or thread in the notes — radiator, reservoir and fuel caps are not interchangeable. Read more

4 Coolant Reservoir Cap parts for the 2021 Honda Clarity come from 2 brands — MOTORAD and CALORSTAT. 1 part fits every engine; the other 3 are engine-specific.

Listed part numbers: CALORSTAT RC0174, MOTORAD T108 and MOTORAD T128, plus the other parts above.

This table covers the radiators that dump engine heat to airflow through the core. Typical signs include overheating in traffic, a wet core, or coolant that disappears with no puddle. Replace the cap if it cannot hold the rated pressure, and bleed the system after the swap. Read more

4 Radiator parts are listed for the 2021 Honda Clarity, from GPD, TECHPRO, AGILITY and 1 other brand. 3 parts fit every engine; the other 1 is engine-specific.

Economy: 2 parts, from GPD and TECHPRO. A representative part number is GPD 13823C.

The Standard Replacement section: 2 options from AGILITY and OSC. AGILITY 8013823 is listed in this group.

Part numbers include GPD 13823C, TECHPRO HO3010253 and AGILITY 8013823, among others listed above.

This table covers the caps that hold system pressure at the radiator or reservoir neck. Typical signs include a leak at the neck, a cap that will not hold pressure, or a missing tether. Match the pressure rating or thread in the notes — radiator, reservoir and fuel caps are not interchangeable. Read more

3 Radiator Cap parts are listed for the 2021 Honda Clarity, from MOTORAD and CALORSTAT.

The Locking Replacement section lists 1 option from MOTORAD — grouped under the catalog's "Locking Replacement" designation — the notes column spells out what sets them apart. MOTORAD ST37 is listed in this group.

The Standard Replacement section: 2 options from CALORSTAT and MOTORAD. CALORSTAT RC0040 is listed in this group.

This group includes MOTORAD ST37, CALORSTAT RC0040 and MOTORAD T37.

This table covers the fan assemblies (and clutches, where listed) that pull air through the radiator. Read more

This group shows a single part: TECHPRO HO3115177.

This table covers the Radiator insulators. Read more

This group shows a single part: TECHPRO HO3013100.

This table covers the Radiator Mount bushings. Typical signs include a clunk over bumps, or a torn or walked-out bushing you can see. Press the new bushing square. A cocked bushing will tear in a few thousand miles. Read more

2 Radiator Mount Bushing parts for the 2021 Honda Clarity come from DORMAN. 1 part fits every engine; the other 1 is engine-specific.

This group includes DORMAN 927241 and DORMAN 927240.

This table covers the senders that report coolant temperature to the gauge or ECU. Typical signs include a gauge that sits on empty or overheat, or a lamp that does not match what the engine is doing. Rule out the cluster and the wiring before replacing the sender. Read more

9 Temperature Sender / Sensor parts are listed for the 2021 Honda Clarity, from WALKER PRODUCTS, CALORSTAT, GPD and 5 other brands. WALKER PRODUCTS 2111080 carries the "Popular" badge. 3 parts fit every engine; the other 6 are engine-specific.

Economy: 3 parts, from CALORSTAT, GPD and UNITED MOTOR PRODUCTS. A representative part number is CALORSTAT WS3039.

The Standard Replacement section: 5 options from WALKER PRODUCTS, WELLS, BECK/ARNLEY and 1 other brand. WALKER PRODUCTS 2111080 is listed in this group.

1 ungrouped part is not assigned to a grade, with the same engine-level match.

This group includes WALKER PRODUCTS 2111080, CALORSTAT WS3039 and GPD 1712488 and the remaining parts above.

This table covers the thermostats that open the coolant circuit at the specified temperature. Typical signs include slow warm-up, a gauge that climbs in traffic, or heat that never quite arrives. Replace the housing gasket with the thermostat and bleed the system so a trapped air pocket does not cook the new part. Read more

3 Thermostat parts for the 2021 Honda Clarity come from 3 brands — AISIN, BECK/ARNLEY and MOTORAD.

This group includes AISIN THH022, BECK/ARNLEY 1430990 and MOTORAD 1214172.

This table covers the seals at the thermostat housing and water outlet. Typical signs include a wet housing, a drip after sitting, or fluid flung off a rotating shaft. Fix the surface the seal rides on. A new seal on a grooved shaft will leak again. Read more

3 Thermostat / Thermostat Housing / Water Outlet Seal parts are listed for the 2021 Honda Clarity, from ELRING, FEL-PRO and MAHLE / CLEVITE.

Part numbers include ELRING 108130, FEL-PRO 35741 and MAHLE / CLEVITE C32021.

This table covers the pumps that circulate coolant through the block and radiator. Typical signs include coolant at the weep hole, pulley play, or a growl from the front of the engine. Replace the thermostat and refill with the specified coolant whenever the pump comes off. Read more

9 Water Pump parts for the 2021 Honda Clarity come from 6 brands — AISIN, FOUR SEASONS, NISSENS and 3 other brands. The "Popular" part is US MOTOR WORKS US8185.

The Economy section: 3 options from US MOTOR WORKS, BECK/ARNLEY and SKP. US MOTOR WORKS US8185 is listed in this group.

Standard Replacement: 4 parts, from AISIN, FOUR SEASONS and NISSENS. A representative part number is AISIN WPH079.

2 further parts sit outside the graded sections, with the same engine-level match.

Part numbers include US MOTOR WORKS US8185, BECK/ARNLEY 1312544 and SKP SKUS8185, among others listed above.

This table covers the gaskets between the water pump and the block or housing. Typical signs include seepage at the joint, a burnt-oil smell, or a leak that appears only after a long drive. Clean both flanges and torque in the sequence the notes or the manual call for. Read more

2 Water Pump Gasket parts are listed for the 2021 Honda Clarity, from FEL-PRO and MAHLE / CLEVITE.

This group includes FEL-PRO 36174 and MAHLE / CLEVITE K32737.