1974 MG MGB 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 1974 MG MGB, from PEAK, PRESTONE, FVP and 1 other brand. FVP MV5050GAL carries the "Popular" badge. All of them fit every engine offered in the 1974 MGB.

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 Heavy Duty section lists 1 option from VALVOLINE — rated for severe service. VALVOLINE ZXG051 is listed in this group.

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 6 options from PEAK, FVP and PRESTONE — built to original-equipment specification. FVP GREEN5050GAL is listed in this group.

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

2 Cooling System Tester Adapter parts are listed for the 1974 MG MGB, from ACDELCO and MOTORAD.

This group includes ACDELCO 12A01 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

5 Radiator Cap parts are listed for the 1974 MG MGB, from MOTORAD, CALORSTAT and ACDELCO.

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 ST9 is listed in this group.

The Standard Replacement section: 3 options from ACDELCO, CALORSTAT and MOTORAD. ACDELCO RC6 is listed in this group.

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

Part numbers include MOTORAD ST9, ACDELCO RC6 and CALORSTAT RC0060, among others listed above.

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

3 Radiator Hose parts for the 1974 MG MGB come from 3 brands — ACDELCO, GATES and ÜRO PARTS.

The Economy section: 2 options from ACDELCO and GATES. ACDELCO 31608 is listed in this group.

Standard Replacement: 1 part, from ÜRO PARTS. A representative part number is ÜRO PARTS GRH305.

This group includes ACDELCO 31608, GATES 25249 and ÜRO PARTS GRH305.

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

One part is listed for the 1974 MG MGB — STANDARD MOTOR PRODUCTS TS233.

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

25 Thermostat parts for the 1974 MG MGB come from 3 brands — MOTORAD, GATES and BECK/ARNLEY. The "Popular" part is MOTORAD 2000160.

The Economy section: 5 options from MOTORAD and GATES. GATES 33508 is listed in this group.

Heavy Duty: 3 parts, from MOTORAD. A representative part number is MOTORAD 5200160.

The Performance section lists 4 options from MOTORAD — engineered beyond original-equipment specification. MOTORAD 2000160 is listed in this group.

Premium: 3 parts, from MOTORAD. A representative part number is MOTORAD 7200180.

Standard Replacement: 10 parts, from MOTORAD, BECK/ARNLEY and GATES. A representative part number is MOTORAD 200195.

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

5 Thermostat / Thermostat Housing / Water Outlet Seal parts are listed for the 1974 MG MGB, from GATES, BECK/ARNLEY, MAHLE / CLEVITE and 2 other brands. GATES 33655 carries the "Popular" badge.

Listed part numbers: GATES 33655, BECK/ARNLEY 0390004 and MAHLE / CLEVITE C24093, plus the other parts above.

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 for the 1974 MG MGB come from 3 brands — FVP, US MOTOR WORKS and GMB.

The Economy section: 2 options from FVP and US MOTOR WORKS. FVP US9082 is listed in this group.

Standard Replacement: 2 parts, from FVP and GMB. A representative part number is FVP 1131050.

Listed part numbers: FVP US9082 and FVP 1131050, plus the other parts above.