1981 Honda Prelude 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

21 Coolant / Antifreeze parts for the 1981 Honda Prelude come from 5 brands — PEAK, PRESTONE, VALVOLINE and 2 other brands. The "Popular" part is FVP MV5050GAL.

In the Compatible With All Colors grade, PRESTONE supplies 1 part: grouped under the catalog's "Compatible With All Colors" designation — the notes column spells out what sets them apart. A representative part number is PRESTONE AF3055.

The Economy section lists 4 options from FVP, PEAK, PRESTONE and 1 other brand — the catalog's value-priced group. FVP MV5050GAL is listed in this group.

In the Premium grade, PRESTONE and PEAK supply 5 parts: a step above OE specification in materials, tolerances or warranty terms. A representative part number is PRESTONE AF2100.

In the Standard Replacement grade, PEAK, VALVOLINE, BECK/ARNLEY and 2 other brands supply 11 parts: built to original-equipment specification. A representative part number is VALVOLINE ZXEL1.

This table covers the adapters used to pressure-test this cooling system. Read more

3 Cooling System Tester Adapter parts for the 1981 Honda Prelude come from 3 brands — ACDELCO, GATES and MOTORAD.

This group includes ACDELCO 12A01, GATES 31413 and MOTORAD 3003.

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

7 Radiator Cap parts for the 1981 Honda Prelude come from 4 brands — GATES, MOTORAD, SKP and 1 other brand. The "Popular" part is GATES 31527.

In the Locking Replacement grade, GATES, MOTORAD and SKP supply 3 parts: grouped under the catalog's "Locking Replacement" designation — the notes column spells out what sets them apart. A representative part number is GATES 31511.

Standard Replacement: 4 parts, from GATES, MOTORAD, CALORSTAT and 1 other brand. A representative part number is GATES 31527.

Listed part numbers: GATES 31527, GATES 31511 and MOTORAD ST13, plus the other parts above.

This table covers the petcocks used to drain the radiator. Read more

One part is listed for the 1981 Honda Prelude — DORMAN 490236.

This table covers the upper, lower and connecting hoses between radiator, engine and reservoir. Typical signs include swelling, cracks, a soft spot, or a leak at a clamp. Replace adjacent aged hoses while the system is drained — they share the same heat cycle. Read more

5 Radiator Hose parts are listed for the 1981 Honda Prelude, from GATES, DAYCO and ACDELCO. GATES 20896 carries the "Popular" badge.

This group includes GATES 20896, ACDELCO 24057L and DAYCO 71049 and the remaining parts above.

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

5 Temperature Sender / Sensor parts for the 1981 Honda Prelude come from 5 brands — ULTRA-POWER, BECK/ARNLEY, ROSTRA and 2 other brands.

The Economy section: 1 option from ULTRA-POWER. ULTRA-POWER 1T1141 is listed in this group.

Standard Replacement: 4 parts, from BECK/ARNLEY, ROSTRA, STANDARD MOTOR PRODUCTS and 1 other brand. A representative part number is BECK/ARNLEY 2010866.

This group includes ULTRA-POWER 1T1141, BECK/ARNLEY 2010866 and ROSTRA 680090 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

20 Thermostat parts are listed for the 1981 Honda Prelude, from MOTORAD, FACET, BECK/ARNLEY and 4 other brands. GATES 33488S carries the "Popular" badge.

The Heavy Duty section lists 2 options from GATES and MOTORAD — rated for severe service. GATES 33488S is listed in this group.

In the Performance grade, MOTORAD supplies 1 part: engineered beyond original-equipment specification. A representative part number is MOTORAD 2040180.

The Premium section: 2 options from MOTORAD. MOTORAD 7240180 is listed in this group.

The Standard Replacement section: 15 options from FACET, MOTORAD, BECK/ARNLEY and 4 other brands. MOTORAD 240180 is listed in this group.

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

13 Thermostat / Thermostat Housing / Water Outlet Seal parts for the 1981 Honda Prelude come from 7 brands — FEL-PRO, APEX, MOTORAD and 4 other brands. The "Popular" part is FEL-PRO 35316.

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

4 Water Pump parts are listed for the 1981 Honda Prelude, from FVP, US MOTOR WORKS and GMB.

Economy: 2 parts, from FVP and US MOTOR WORKS. A representative part number is FVP US9029.

The Standard Replacement section: 2 options from FVP and GMB. FVP 1351161 is listed in this group.

Part numbers include FVP US9029 and FVP 1351161, 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

This group shows a single part: APEX AWP3211.