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The best car radiators leak sealant in comparison

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Holts Sealit Leak Repair 250ml, (Packing May Vary)

Holts

12% off

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9,9

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Mixes with all types and colours of antifreeze coolant
Easy to use, simply pour and go

£ 11.49

£ 14.01

£ 14.59

£ 15.59

Wynn's Radiator Stop-Leak - Seals Radiator & Head Gasket Leaks - Prevents Corrosion & Rust - Compatible with All Coolants/Antifreeze & OAT Fluids - Safe for Hoses & Sensors - 325ml

Wynn's

3% off

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9,8

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VERSATILE APPLICATION FOR PETROL, DIESEL, AND LPG ENGINES Ideal for all "water" cooled systems, this sealant is suitable for a wide range of engine types, including petrol, diesel, and LPG. It is recommended not only for repairing minor leaks but also as a preventive solution to avoid potential issues before they escalate into costly repairs. By reinforcing the integrity of the cooling system, this product helps maintain vehicle reliability and performance under various driving conditions. Whether used for routine maintenance or emergency repairs, it offers an effective and lasting solution for cooling system leaks.
PREVENTS CLOGGING AND ENSURES TEMPERATURE SENSOR ACCURACY Unlike some sealing products that can lead to buildup and reduced efficiency, this formulation is designed to avoid clogging radiator waterways and temperature sensors. By maintaining proper coolant flow and accurate temperature readings, this product ensures that the engine operates within the ideal temperature range, preventing overheating or inefficiencies. Its compatibility with various antifreeze and coolant types makes it a versatile and reliable choice for ongoing maintenance and preventive care.
ENHANCED PROTECTION AGAINST CORROSION AND RUST Offering more than just leak prevention, this product also provides enhanced protection against corrosion and rust. Exposure to heat, moisture, and coolant chemicals can lead to internal corrosion, weakening the system and leading to expensive repairs. This advanced formulation actively protects metal components from rust and corrosion, helping to maintain engine efficiency and prolong the lifespan of the cooling system. Its compatibility with OAT (organic acid technology) fluids and all standard antifreeze products ensures easy integration into any system.

£ 6.29

£ 8.79

Recommendation

K-Seal HD Coolant Leak Repair, 472ml | HGV Radiator, Block & Head Gasket Sealant

K-Seal

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9,8

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EASY TO USE K-Seal couldn't be simpler & requires no draining or flushing; just shake, pour & go - shake the bottle, add the fluid to your coolant system & run your engine as normal.
STOP HOLES & CRACKS With 1 step our unique formula will seek out each hole & crack, permanently sealing them, without any adverse impact on the efficiency of your engine cooling.
HEAVY DUTY PERFORMANCE Engineered for large engines & industrial use; suitable for commercial or agricultural vehicles. A permanent repair for the lifetime of the engine. Compatible with all types of antifreeze coolant.
PROFESSIONAL-GRADE RELIABILITY Trusted by mechanics, our non-corrosive sealer delivers a durable & long-lasting repair, without clogging your cooling system. A cost-effective solution to engine coolant leaks, enhancing the reliability & performance of your vehicle s cooling system. We've sold millions worldwide & are independently verified by university testing to meet ASTM D3147.

£ 22.99

£ 20.90

ERRECOM Extreme - 30mL, Leak Stop for Vehicle A/C Systems, includes R134a adapter

ERRECOM

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9,6

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SAFE for the system thanks to its polymer-free formulation; does not block the refrigerator and does not react with moisture and oxygen
ACTS QUICKLY on rubber and metal components of A C systems

Facom 006012 Anti-Leak Engine Cooling System Radiator Sealant 250ml

Facom

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9,5

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Stops cooling liquid leakage. Prevents engine from overheating
Ideal product for regular use
Very good quality product

LIQUI MOLY Pro-Line Radiator Stop Leak K | 250 ml | Cooler additive | SKU: 5178

Liqui Moly

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9,5

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Used for sealing small leaks in cooling circuits of passenger motor vehicles, commercial vehicles and buses. Also suited for cooling water circuits equipped with water filters.
Contents will treat up to 40 liters of coolant.
Small leaks caused by stone impacts, porous soldering points and hairline cracks in the cooling simple are easy to localize (one notices that the cooling water level is sinking).
Shake container before use. Start up the heater. With the engine running, pour the contents into the coolant at operating temperature and allow the engine to continue running for at least a further 10 minutes.

ARZER Car Radiator & Hose Stop Leak Repair Additive - Anti Corrosion 250ml - Repairs Weld Cooling System Rads

ARZER

9,4

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Bar's BARSTML2L91 Manual Transmission Leak Sealant Additive, 200 ml

Bars

65% off

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9,4

Offer ends in:

04Days

10hours

03minutes

19seconds

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Non-corrosive and non-clogging.
Stops leaks in manual transmissions and ensures gaskets and seals remain flexible.
Stops transmission fluid leaks

Granville Genuine 1 X Petro Patch Putty 50g Multi Purpose Metal Repair Leaks Car Sealant - Part Number 455

okoium

3% off

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9,3

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Premium Product

Liquid Waterproof Sealant, Hupeyna Invisible Waterproof Agent, Transparent Repairing Leak Waterproof Adhesive, Indoor and Outdoor Water-Based Waterproof Coating 35 Ounces

Hupeyna

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9,3

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Practical & High Quality Liquid waterproofing sealants coatings are water-based. Multiple overlapping coats form a permanent bond. Invisible waterproof glue forms a film that insulates against air, water and moisture. The roof sealant waterproof is waterproof, long-lasting waterproof, low temperature and heat resistant. The use of transparent repairing leak waterproof adhesive can form a long-term protective film, which helps to save time, money and energy.
Transparent Waterproof Glue is Easy to Use Mix the invisible waterproof glue well before use. Brush, roll, wipe, dip or pour, you can use the brush to dip and wipe, roller to apply, pour and then apply. The liquid waterproof sealant is applied evenly, and the self-leveling formula can smoothly cover and penetrate small gaps and cracks, and play a sealing role. Water-based waterproof sealant is suitable for both indoor and outdoor use.
Liquid Waterproof Sealant Coverage Each 1 kg of product covers approximately 14 sq ft (1.3 sq m). Apply in 3-4 thick layers. Waterproof coating adheres easily to surfaces, repairing holes, cracks, crevices, tears and leaks, and sealing any cracked surfaces. Roof sealant waterproof also forms a protective waterproofing layer in the immediate area.
Liquid Waterproof Sealant Protect Surfaces and Repair Leaks Use on - Flat roofs, sloped roofs, roofs, external wall cracks, foundations, sheds, basements, metal, wood, concrete, gutters, skylights, chimneys*, PVC pipe joints, windows, RVs, DIY projects, external walls pipeline, seals pipeline leaks, walls, corners, toilet leaks, substrate joints, car roofs, pools, baths and more.
Invisible Waterproof Agent Cold and Wet Tip Prolonged rainy and wet weather, falling temperatures can cause waterproof adhesive to take longer to cure. We recommend that you try to ensure that the weather is sunny and the operating environment is relatively dry before and after applying the waterproof glue. Liquid rubber sealant use temperature 10 C 50 F or higher (including overnight temperatures).

This ranking is created through algorithmic analysis of millions of products tailored specifically to your search. We aim to find the most suitable product for you based on manufacturer information and price. The ranking reflects our opinion and should serve as a good starting point for your purchase. We would like to point out that we have not tested the products ourselves and link to selected online shops and partners from which we may receive compensation.

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Gorilla 84756 Waterproof Coat & Seal Black 473ml

Design & durable

~~£ 78.85~~

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5in1 Radiator Stop Leak 310ml

Added corrosion inhibitors

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Granville Ce-Lit Radiator Stop Leak Cement Sealant Powder (1)

Granville Ce Lit Radiator Stop Leak Cement Sealant Powder 1

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Waterproof Sealant Clear 2L(70 oz), Wadities Wall Bathroom Roof Water-Based Waterproof Coating, Invisible Repairing Leak Liquid Rubber Sealant for Indoor & Outdoor

Easy to Operate Apply by roller or brush above 10 C 50 F (including overnight temperatures). Apply evenly to ensure coverage and penetration into the cracks, and play a sealing role. For good waterproofing, 2-3 coats are required. Allow to dry to the touch with no moisture underneath before applying the next coat. A waterproof layer can be formed after 48-72 hours, and the waterproof layer will become stronger over time.

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K-Seal Permanent Coolant Leak Repair for Cooling Systems Head Gaskets Radiators

No flushing. Just shake, pour and go.

free shipping

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Polar Clear Leak Fix Spray - 400ml - Waterproof Roof Sealant - Instantly Seals Leaks and Cracks, for Lasting Protection on Roofs, Drainpipes and Gutter Repairs, for Interior and Exterior Use

Advanced Waterproofing Solution Polar Clear LeakFix spray is an innovative waterproof sealant spray designed to address fine leaks and cracks effectively. Its rubberised protective formula provides dependable protection against water damage, ensuring long-lasting results on various surfaces including flat roofs, gutters, and external pipes.

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flintronic RTV Engine Sealant, 650°F High Temperature Silicone Sealant, Oil and Water Resistance Anti-Freeze Sealing for Automotive Motorbike Machine Equipment Repairing, 70ml Silicone Gasket Sealant

HIGH QUALITY MATERIAL Room temperature vulcanized RTV silicone sealant and adhesive, chemically formulated for high strength bonding. Safe, low odor, non-corrosive, excellent adhesion. The paste is red in color and resistant to water, steam, oil, transmission oil and antifreeze, and has a temperature range of -62 C to 343 C

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ULTIMATE WATERPROOF SEALANT Stop Leak Sealer Spray provides advanced, long-lasting leak protection for gutters, flat roofs, and more. Jenolite's waterproofing sealant can be trusted to act as an instant leak sealer. Perfect for fast-fix repairs and protection for guttering, flat roofs, shed roofs, drain pipes, caravans and more.

~~£ 13.99~~

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AMK® Holts Sealit Coolant Leak Repair Stops Radiator Head Gasket Engine Block Leaks Permanently Antifreeze Compatible Fast Acting

AVOIDS COSTLY REPAIRS By providing a permanent seal, this product can help you avoid expensive mechanical repairs, such as head gasket replacement. Offers great value for money.

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Carlube Radiator Sealer 500ml – Fast Leak Repair, Prevents Future Leaks, Safe & Compatible with All Antifreeze

FAST LEAK REPAIR Carlube Radiator Sealant quickly repairs leaking radiators, providing an immediate solution to prevent further damage and coolant loss.

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Slime CRK0305 - IN Flat Tyre Puncture Repair, Smart , Emergency Kit for Car Tyres, Includes Sealant and Inflator Pump, Suitable for Cars and Other Highway Vehicles, 15 Min Fix

Tyre Pressure Monitoring System (TPMS) Safe

~~£ 25.33~~ free shipping

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Permatex 30301 Radiator Repair - Stop Leak, 16 fl oz, Protecting Against Coolant Loss, Stopping Leaks and Seepage from Head Gaskets

Peace of Mind With Permatex Radiator - Stop Leak, You Can Drive With The Peace of Mind Knowing That Your Engine is Protected, and Your Car is Running Smoothly.

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The best car radiators leak sealant in comparison

Guaranteed independent and reliable

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