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Würth Radiator Sealant – 400 ml | Stop Leaks and Protect Your Engine
£9.25
Würth Radiator Stop Leak 400ml is a professional cooling system sealant designed to help seal minor leaks and hairline cracks in radiators, engine blocks, cylinder heads and hose connections. Its easy-to-use formula helps reduce coolant loss and maintain cooling system performance.
- Effective Leak Sealing – Helps seal minor leaks and hairline cracks.
- Reduces Coolant Loss – Supports normal cooling system operation.
- Versatile Application – Suitable for compatible radiators, engine blocks and cooling components.
- Material Compatible – Designed for use with common radiator materials, rubber and plastic parts.
- Easy Application – Add to the cooling system following the manufacturer’s instructions.
Size: 400ml
Important: Not suitable for cooling systems fitted with dirt strainers.
Explore our Würth Cooling System Maintenance range for related products.
| Quantity | Discount | Discounted price |
| 1 - 3 | - | £9.25 |
| 4 - 7 | 5% | £8.79 |
| 8 - 12 | 8% | £8.51 |
| 13 - 18 | 10% | £8.33 |
| 19 - 24 | 15% | £7.86 |
Description
Würth Radiator Stop Leak 400ml – Cooling System Leak Sealant
Würth Radiator Stop Leak is a professional cooling system sealant developed to help seal minor leaks and hairline cracks in vehicle radiators and compatible engine cooling components. Designed to reduce coolant loss and help maintain cooling system performance, this easy-to-use formula provides a practical solution for suitable small leaks in radiators, engine blocks, cylinder heads and hose connections.
Effective Radiator Sealant for Minor Cooling System Leaks
Würth Radiator Stop Leak is designed to help seal hairline cracks and small leaks within compatible vehicle cooling systems, reducing coolant loss and helping maintain normal system operation.
Coolant loss can contribute to engine overheating and mechanical damage if left unresolved. This specialist radiator sealant provides a convenient treatment for suitable minor leaks without immediately requiring component replacement.
The formula is intended for use with common radiator materials and is designed not to adversely affect compatible rubber and plastic cooling system components when used as directed.
Suitable application areas include radiators, engine blocks, cylinder heads and hose connections where minor leakage is present.
For additional maintenance products, explore our Würth Cooling System Maintenance range.
Key Features
- Seals Minor Cooling System Leaks – Designed for hairline cracks and small leaks in compatible cooling system components.
- Helps Reduce Coolant Loss – Supports coolant retention and normal cooling system operation.
- Multiple Application Areas – Suitable for minor leaks in radiators, engine blocks, cylinder heads and hose connections.
- Material Compatibility – Formulated for use with common radiator materials and compatible rubber and plastic components.
- Simple Application – Add to the cooling system according to the manufacturer’s instructions.
Technical Specifications
- 400mlContainer Size
- 10 MinMinimum Engine Run Time
- MinorLeak Applications
- WürthManufacturer
| Specification | Details |
|---|---|
| Brand | Würth |
| Product Name | Radiator Stop Leak |
| Product Type | Cooling System Leak Sealant |
| Contents | 400ml |
| Primary Application | Sealing Minor Radiator and Cooling System Leaks |
| Suitable Leak Type | Hairline Cracks and Small Leaks |
| Application Areas | Radiators, Engine Blocks, Cylinder Heads and Hose Connections |
| Material Compatibility | Common Radiator Materials and Compatible Rubber / Plastic Components |
| Application Method | Add to Cooling System as Directed |
| Minimum Engine Run Time | 10 Minutes |
| Manufacturer Dosage Reference | 300ml per 10 Litres of Coolant |
| Cooling Systems with Dirt Strainers | Not Suitable |
| Quantity Supplied | 1 × 400ml Container |
| Condition | New |
Dosage Information: The supplied product information states that 300ml is sufficient for approximately 10 litres of coolant. As this listing is for a 400ml container, always confirm the correct treatment quantity against the current product label and manufacturer’s instructions before use.
Important: This product is intended for suitable minor cooling system leaks. It is not a substitute for repairing major cracks, severely damaged components or significant coolant loss.
Why Choose Würth Radiator Stop Leak?
Minor Leak Sealing
Designed to help seal small leaks and hairline cracks in compatible cooling system components.
Helps Maintain Coolant Levels
Reduces coolant loss from suitable minor leaks, helping maintain cooling system performance.
Compatible Materials
Formulated for common radiator materials and suitable rubber and plastic components.
Convenient Treatment
Simple cooling system application without specialist installation equipment.
Typical Applications
- Minor radiator leaks and hairline cracks.
- Small leaks in compatible engine cooling passages.
- Minor seepage around suitable hose connections.
- Hairline leakage in compatible engine block components.
- Minor cooling system leakage associated with cylinder head components.
- General cooling system maintenance where a suitable leak sealant is specified.
Important: Cooling system leaks should be properly diagnosed before treatment. Major leaks, overheating, coolant contamination, head gasket failures or significant pressure loss require professional inspection and appropriate mechanical repair.
Application & Instructions
Follow the current Würth product label and vehicle manufacturer’s cooling system recommendations.
- Inspect the Cooling System: Identify the source and severity of coolant loss. Confirm that the leak is suitable for treatment with a radiator sealant.
- Check Compatibility: Ensure the vehicle’s cooling system is compatible and does not contain a dirt strainer.
- Prepare the Product: Shake the container thoroughly before use.
- Warm the Engine: Bring the cooling system to the temperature specified in the manufacturer’s instructions, then allow it to reach a safe condition for opening.
- Add the Sealant: Introduce the recommended quantity into the cooling system through the appropriate filling point, following the product and vehicle instructions.
- Circulate the Product: Run the engine for at least 10 minutes, as specified in the supplied product instructions, while monitoring coolant temperature.
- Check the System: After treatment, inspect for continued leakage and verify the coolant level once the system has cooled safely.
Safety Warning: Never open a hot or pressurised radiator or coolant expansion tank. Hot coolant can cause serious burns. Allow the cooling system to cool and depressurise before removing any cap.
Important: If the leak persists, coolant loss continues or the engine overheats, stop using the vehicle and arrange professional diagnosis.
Important Usage Information
- Minor Leaks Only – Intended for hairline cracks and small cooling system leaks.
- Dirt Strainers – Do not use in cooling systems fitted with dirt strainers.
- Correct Dosage – Follow the current Würth instructions for the system’s coolant capacity.
- Vehicle Compatibility – Confirm suitability for the vehicle and cooling system design.
- Mechanical Damage – Major leaks and damaged components require appropriate repair or replacement.
- Monitor Performance – Check coolant levels and cooling system operation after treatment.
More Würth Cooling System Maintenance Products
Explore our Würth Cooling System Maintenance range for additional products designed to support radiator and engine cooling system care.
For other professional automotive consumables, browse our Würth Products collection.
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Choose Würth Radiator Stop Leak 400ml for treating suitable minor radiator and cooling system leaks. Designed to help seal hairline cracks and reduce coolant loss, this professional sealant provides a convenient solution for compatible vehicle cooling systems. Order genuine Würth maintenance products from Ace Consumables today.
Brand
WÜRTH
Würth: Trusted Tools, Equipment, and Consumables for Every Industry
Würth is a global leader in providing high-quality tools, equipment, and consumables across various industries. With a strong reputation for reliability and innovation, the company consistently delivers top-tier products. Whether you work in automotive, construction, or industrial sectors, they offer products that meet your specific needs.[show_more more="Read more" less="Read less"]Why Choose Würth?
Würth offers a vast selection of tools, equipment, and consumables. For example, they provide everything from hand tools to industrial supplies, including essential consumables like cleaning products, aerosol sprays, greases, and lubricants. So, no matter how specialized your job is, you can find the right tool or consumable here.Superior Quality
Wurth ensures that their tools and consumables deliver reliable performance. In fact, each product, whether a tool or a lubricant, undergoes rigorous testing to meet the highest standards. Consequently, this commitment to quality guarantees that you receive durable and effective solutions every time.Innovation and Technology
Würth stays ahead by integrating the latest technological advancements into their product lines. Their tools and consumables, such as cleaning sprays and lubricants, are specifically designed to enhance performance and simplify your work. Therefore, this focus on innovation keeps the company at the forefront of the industry.Global Expertise with Local Support
With operations in over 80 countries, this global leader combines expertise with local knowledge. This ensures their supplies are trusted worldwide while being tailored to local needs. Moreover, you can always count on consistent support and service, no matter where you are.Sustainability and Responsibility
Würth prioritizes sustainability in their products and practices. They offer eco-friendly consumables, including cleaning agents and aerosols, which are designed with environmental responsibility in mind. As a result, by choosing these products, you contribute to reducing environmental impact while maintaining high performance.Applications and Industries
Automotive: They supply a full range of automotive tools and consumables, including fasteners, greases, and aerosol sprays, ensuring your workshop is fully equipped. Construction: From hand tools to lubricants, their products help you manage any construction project, providing reliable solutions for tasks of all sizes. Industrial: Their equipment and consumables, such as industrial-grade lubricants and cleaning products, are specifically designed to meet the demands of heavy-duty industrial environments. They deliver high performance under pressure.In summary, Wurth stands out as the top choice for professionals seeking reliable tools, equipment, and consumables. Their blend of quality, innovation, and sustainability makes them a brand you can trust. Therefore, explore their products today and discover why they are the preferred choice for your tool, equipment, and consumable needs.[/show_more]
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