K-Seal®

Permanently seals leaks in the head, head gasket, block,
radiator, heater matrix and water pump.

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K-Seal

Permanent Coolant Leak Repair with K-Seal

Coolant leaks don’t have to result in costly repair bills – simply add K-Seal to your coolant system for a quick and permanent fix. K-Seal is scientifically tested, trusted by millions of customers worldwide, and the only coolant leak repair fluid carried by the AA, the UK’s largest roadside repair company.

Just pour & go

K-Seal couldn’t be simpler to use. Just shake the bottle, add the fluid to your coolant system, and run your engine as normal. K-Seal’s unique formula will seek out holes and cracks, and permanently seal them, with no adverse impact on the efficiency of your engine cooling.

Just had to send a big thank you for fixing a leak in my Fiat Seicento Sporting radiator, it really does do what it says! The leak was cured in 1 minute flat and saved me the price of a new radiator (£100). Thanks again!

Dave Locke, UK View more case studies

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How to use K-Seal

1. Shake the bottle vigorously and add the entire contents to the radiator or header/expansion tank

If adding to the radiator do not pour directly onto the radiator core. K-Seal products are compatible with all types of antifreeze / coolant and are not affected by other additives that may already be in the cooling system.

It does not matter if you add K-Seal products to a cold or hot engine but take care when working with a hot engine.

For very small cooling systems e.g. motorbikes, it is possible to add just part of the bottle but you must make sure that the contents are extremely well mixed first.

2. Run the engine up to operating temperature

The quickest way is to take the vehicle for a gentle drive otherwise leave the engine idling until the temperature gauge reaches the normal level.

3. Either replace the cooling system contents or leave K-Seal in the system

After K-Seal has made a repair it is not necessary to leave it in the system because the repair is permanent. You can either choose to replace the contents of the cooling system or leave the original K-Seal product in the system.

Important Please use extreme caution when working on a hot cooling system as hot coolant and gases could cause injury. If in doubt please consult a qualified mechanic.

Watch the video on how to use K-Seal

FAQs

Is K-Seal compatible with all types of coolant?

Yes. K-Seal does not react with coolant or other additives that may already be present in the system.

Is there any special preparation I need to do before using K-Seal?

Unlike other block sealers, K-Seal is a simple ‘pour & go’ solution. Shake the bottle well and then add the entire contents to the cooling system where you would normally top up the coolant/water.

How much K-Seal do I need?

1 standard bottle of K-Seal (236ml/8floz) will treat cooling systems with a capacity up to 20 litres (this covers motorbikes up to light commercial vehicles). For larger cooling systems use our Heavy Duty (472ml/16floz) size K-Seal.

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Expert Advice

Head Gasket Failure? Cracked Head or Block?
Leaking Radiator?

Expert Advice

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Have any of these symptoms? K-Seal could save you thousands on a workshop repair. Search for a stockist today!