Radiator Caps for Cooling System Pressure and Safety

Choose from a wide selection of radiator caps designed to regulate pressure and maintain safe cooling system operation. Whether you need a standard cap for a daily driver or a high-pressure cap for a performance build, this collection offers quality-tested components for reliable fit and function.

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Instrument Voltage StabiliserInstrument Voltage Stabiliser
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Instrument Voltage Stabiliser

Instrument Voltage Stabiliser
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Classic Style Paper Covered Aluminium Ducting 80mm I.D. - Car Builder SolutionsClassic Style Paper Covered Aluminium Ducting 30-100mm
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Classic Style Paper Covered Aluminium Ducting 30-100mm

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£8.40
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G Clamps 50mm to 200mmG Clamps 50mm to 200mm
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G Clamps 50mm to 200mm

G Clamps
£4.20
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Single Relay Plug with Terminals

Single Relay Plug with Terminals

Durable 5-terminal relay plug with 1/4" female crimp terminals for secure connections in automotive/electrical applications. Easy installation, reliable performance.
£3.00
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Brake and Clutch Reservoir Bleeding Adapter

Brake and Clutch Reservoir Bleeding Adapter

RESERVOIR BLEEDING ADAPTER
£19.20
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3 Piece Locking Clamping Pliers Set For Flexible Hoses3 Piece Locking Clamping Pliers Set For Flexible Hoses

3 Piece Locking Clamping Pliers Set For Flexible Hoses

Will clamp between 6mm and 57mm hose.
£7.20
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3 Watt LED White/Red Rechargeable Headband Lamp

3 Watt LED White/Red Rechargeable Headband Lamp

USB charging cable included Up to 3 hours battery life
£7.80
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Demist Vent 87mm x 14mmDemist Vent 87mm x 14mm

Demist Vent 87mm x 14mm

ABS demist vent, 87mm x 14mm, fits 71mm x 8mm hole. Ideal for boats and caravans. Clears condensation.
£6.00
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Silver Chrome Paint AerosolSilver Chrome Paint Aerosol

Silver Chrome Paint Aerosol

This plated finish paint aerosol delivers a brilliant, very shiny silver finish. Easy to apply and perfect for various projects.
£13.20
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Large Internal Naca Duct Black 270mmLarge Internal Naca Duct Black 270mm

Large Internal Naca Duct Black 270mm

Can be bonded or riveted to body.
£19.20
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Naca Duct Internal Carbon Effect Small

Naca Duct Internal Carbon Effect Small

Can be bonded or riveted to body. 180mm x 145mm x 25mm high
£14.40
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£14.40
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Naca Duct Internal Carbon Effect Large

Naca Duct Internal Carbon Effect Large

Can be bonded or riveted to body. 235mm x 190mm x 45mm high.
£16.80
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360mm LED Interior Strip Light360mm LED Interior Strip Light

360mm LED Interior Strip Light

Overall size. 30mm x 23mm x 11mm high.
£30.00
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440 Amp Jump Start Posts

440 Amp Jump Start Posts

SOLD AS A PAIR
£24.00
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Fuel Tank Pick Up Pipes
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Fuel Tank Pick Up Pipes

Fuel tank pick up pipes
£24.00
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Smiths GPS Speed Sensor for Electronic SpeedometersSmiths GPS Speed Sensor for Electronic Speedometers

Smiths GPS Speed Sensor for Electronic Speedometers

Smiths GPS Speed Sensor for Electronic Speedometers
£162.00
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Smiths Inductive Speed Sensor for Electronic SpeedometersSmiths Inductive Speed Sensor for Electronic Speedometers

Smiths Inductive Speed Sensor for Electronic Speedometers

Smiths Inductive Speed Sensor for Electronic Speedometers
£86.40
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Copper Brake Pipe 22G 25Ft Roll

Copper Brake Pipe 22G 25Ft Roll

High-quality copper/nickel brake pipe in 3/16". Rated to 215 Bar, ensuring reliable braking performance.
£15.00
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Copper/Nickel Brake Pipe 22G 25Ft Roll

Copper/Nickel Brake Pipe 22G 25Ft Roll

High-quality copper/nickel brake pipe in 3/16". Rated to 215 Bar, ensuring reliable braking performance.
£21.60
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£21.60
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Brass Compression Union For 6mm Copper , Nylon or Steel PipeBrass Compression Union For 6mm Copper , Nylon or Steel Pipe

Brass Compression Union For 6mm Copper , Nylon or Steel Pipe

Brass compression joiner for 6mm pipe.
£9.60
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Engine Oil

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MOBIL Mobil 1 0W-20 Advanced Full Synthetic Engine Oil

Advanced full synthetic 0W20 motor oil. Optimised for fuel economy and long-lasting engine protection in hybrid vehicles.
£13.96
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CASTROL EDGE 0W-30 A5/B5 Engine Oil

Advanced 0W-30 motor oil boosts engine performance and fuel economy. Trusted by experts for ultimate protection and efficiency.
£13.96
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CASTROL EDGE 5W-40 Fully Synthetic Engine Oil

Advanced full synthetic engine oil for maximum performance and protection. Improves fuel economy and exceeds industry standards.
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MOBIL Super 1000 X1 15W-40 Engine Oil

High-performance 15W40 motor oil. Provides excellent engine cleanliness, high-temperature protection, and wear protection. Suitable for various vehicles.
£33.95
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CASTROL Magnatec 10W-40 A/B Engine Oil

Advanced engine oil with DUALOCK molecules for non-stop protection and reduced warm-up wear. ACEA A3/B4, API SP.
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MOBIL Super 2000 X1 10W-40 Engine Oil

High-performance 10W40 motor oil offering superior engine protection, sludge prevention, and cleanliness. Meets various industry standards.
£7.96
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CASTROL Magnatec 5W-30 A5 Engine Oil

Advanced engine oil with DUALOCK technology for superior protection during warm-up and stop-start driving. Suitable for modern vehicles.
£10.96
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CASTROL GTX 5W-30 RN17 Engine Oil

5W-30 RN17 engine oil. Superior sludge protection and advanced viscosity and thermal breakdown protection. Extends engine life.
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  • Stainless Radiator Cap Valveless - Car Builder SolutionsStainless Radiator Cap Valveless - Car Builder Solutions
    Out Of Stock

    Stainless Radiator Cap Valveless

    Durable stainless steel valveless radiator cap. Secure fit. 79mm width. 56mm neck. Ideal for remote systems.
    £9.00
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    £9.00
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    Out Of Stock
  • radiator-cap-valveless-car-builder-solutionsradiator-cap-valveless-car-builder-solutions

    Radiator Cap Valveless

    Upgrade your cooling system with this valveless radiator cap for use with remote headers or breather tanks.
    £7.20
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  • Long Reach Radiator Cap Rubber Upper Seal 15lb - Car Builder SolutionsLong Reach Radiator Cap Rubber Upper Seal 15lb - Car Builder Solutions

    Long Reach Radiator Cap Rubber Upper Seal 15lb

    Durable, long-reach rubber upper seal for radiator caps. 15lb pressure, 26mm seal-to-seal. Ensures a secure, leak-proof fit.
    £7.20
    £0.00
    £7.20
    (-0%)
  • Radiator Cap Spring Steel Upper Seal 15lb - Car Builder SolutionsRadiator Cap Spring Steel Upper Seal 15lb - Car Builder Solutions

    Radiator Cap Spring Steel Upper Seal 15lb

    Durable radiator cap with spring steel upper seal, standard reach, and 15 lb pressure rating.
    £7.20
    £0.00
    £7.20
    (-0%)
  • Mini Radiator Pressure Cap 13lb - Car Builder SolutionsMini Radiator Pressure Cap 13lb - Car Builder Solutions

    Small Diameter Radiator Pressure Cap 13lb

    Mini radiator pressure cap, 13lb (0.9 bar), 45mm diameter, suitable for modern continental and Japanese vehicles.
    £7.20
    £0.00
    £7.20
    (-0%)
  • Radiator Cap (CHROME) Rubber Upper Seal 15lb - Car Builder SolutionsRadiator Cap (CHROME) Rubber Upper Seal 15lb - Car Builder Solutions

    Radiator Cap (CHROME) Rubber Upper Seal 15lb

    Stylish chrome radiator cap with 15lb pressure rating and rubber upper seal. Durable, leak-proof and easy to install.
    £8.40
    £0.00
    £8.40
    (-0%)
  • Long Reach Radiator Cap Spring Steel Upper Seal 15lb - Car Builder SolutionsLong Reach Radiator Cap Spring Steel Upper Seal 15lb - Car Builder Solutions

    Long Reach Radiator Cap Spring Steel Upper Seal 15lb

    Durable long-reach radiator cap with a spring steel upper seal, suitable for 15lb pressure systems. Features a 26mm seal-to-seal measurement.
    £7.20
    £0.00
    £7.20
    (-0%)
  • Black Valveless Radiator Cap Rubber Seal - Car Builder SolutionsBlack Valveless Radiator Cap Rubber Seal - Car Builder Solutions

    Black Valveless Radiator Cap Rubber Seal

    Durable valveless radiator cap with rubber seal for secure leak prevention and efficient cooling.
    £9.00
    £0.00
    £9.00
    (-0%)
  • Long Reach Stainless Radiator Cap Rubber Upper Seal 7lb - Car Builder SolutionsLong Reach Stainless Radiator Cap Rubber Upper Seal 7lb - Car Builder Solutions

    Long Reach Stainless Radiator Cap Rubber Upper Seal 7lb

    Durable stainless steel radiator cap with rubber seal. Long reach design, 7lb pressure, and 26mm seal-to-seal measurement.
    £9.00
    £0.00
    £9.00
    (-0%)
  • steel-valveless-mini-radiator-pressure-cap-car-builder-solutionssteel-valveless-mini-radiator-pressure-cap-car-builder-solutions

    Valveless Small Diameter Radiator Cap

    Durable plated steel valveless small diameter radiator cap. 45mm diameter, 65mm ear to ear.
    £4.80
    £0.00
    £4.80
    (-0%)
  • Mini Radiator Pressure Cap 18 lb - Car Builder SolutionsMini Radiator Pressure Cap 18 lb - Car Builder Solutions

    Small Diameter Radiator Pressure Cap 18 lb

    A mini radiator pressure cap (1.3 Bar/18 lb) for modern vehicles. 45mm diameter, 65mm ear-to-ear, 19mm seal-to-seal height.
    £7.20
    £0.00
    £7.20
    (-0%)
  • Mini Radiator Pressure Cap 15 lb - Car Builder SolutionsMini Radiator Pressure Cap 15 lb - Car Builder Solutions

    Small Diameter Radiator Pressure Cap 15 lb

    Compact 15 lb radiator pressure cap . 45mm diameter, 65mm ear-to-ear.
    £7.20
    £0.00
    £7.20
    (-0%)
  • Radiator Cap (CHROME) Steel Upper Seal 15lb - Car Builder SolutionsRadiator Cap (CHROME) Steel Upper Seal 15lb - Car Builder Solutions

    Radiator Cap (CHROME) Steel Upper Seal 15lb

    Chrome-plated radiator cap with 15lb pressure rating, standard reach, and durable steel upper seal.
    £8.40
    £0.00
    £8.40
    (-0%)
  • Black Radiator Cap Steel Upper Seal 15lb - Car Builder SolutionsBlack Radiator Cap Steel Upper Seal 15lb - Car Builder Solutions

    Black Radiator Cap Steel Upper Seal 15lb

    Durable 15lb black radiator cap with steel upper seal. Prevents overheating and ensures reliable pressure regulation.
    £9.00
    £0.00
    £9.00
    (-0%)
  • Long Reach Stainless Radiator Cap Rubber Upper Seal 4lb - Car Builder SolutionsLong Reach Stainless Radiator Cap Rubber Upper Seal 4lb - Car Builder Solutions
    Out Of Stock

    Long Reach Stainless Radiator Cap Rubber Upper Seal 4lb

    Durable stainless steel radiator cap with rubber seal, 4lb pressure, and 26mm seal-to-seal measurement.
    £9.00
    £0.00
    £9.00
    (-0%)
    Out Of Stock
  • Radiator Cap Rubber Upper Seal 9lb - Car Builder Solutions
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    Radiator Cap Rubber Upper Seal - Choose Pressure

    Plated Steel radiator cap with a rubber upper seal for optimal cooling system performance and a secure fit.
    £7.20
    £0.00
    £7.20
    (-0%)
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  • Stainless Radiator Cap Rubber Seals 7lb - Car Builder SolutionsStainless Radiator Cap Rubber Seals 4lb - Car Builder Solutions
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    Stainless Radiator Cap - Choose Pressure

    Durable stainless steel radiator cap with rubber seals, and 56mm neck diameter.
    £9.00
    £0.00
    £9.00
    (-0%)
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  • Stainless 7lb Pressure Release Radiator Cap - Car Builder SolutionsStainless 20lb Pressure Release Radiator Cap - Car Builder Solutions
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    Stainless Pressure Release Radiator Cap - Choose Pressure

    Stainless lever radiator cap. Rubber upper and lower seals.
    £12.00
    £0.00
    £12.00
    (-0%)
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