K-Seal® ULTIMATE

A unique formula specially developed to permanently repair serious head gasket and porous block problems

Where to buy

Just Pour & Go – No Need for Expensive Head Gasket Repairs

K-Seal ULTIMATE K3501 Head Gasket Repair is the simple, permanent fix for blown head gaskets, cracked heads and blocks, and porous engine blocks. Guaranteed repair for the life of your engine, or your money back!

Our unique formula works with all water-cooled engines – there’s no need to drain or flush your cooling system, and it doesn’t matter what kind of antifreeze or coolant you’ve used previously. Simply shake the bottle, pour K-Seal ULTIMATE into your cooling system, and you’re back on the road.

Just one bottle of K-Seal ULTIMATE is enough to fix blown head gaskets and cracked heads in cars, SUVs and small trucks. For larger engines, simply use two bottles.




That worked. Thanks for all your help. You saved me three thousand dollars.

Brian Campbell, USA View more case studies

Where to buy K-Seal

Not in New Zealand?

How to use K-Seal ULTIMATE

1. Shake the bottle

K-Seal ULTIMATE will naturally separate if left to sit for an extended period. It’s important to shake the bottle for 30 seconds before application, to ensure an effective treatment.

2. Pour into the radiator

Pour K-Seal ULTIMATE into your radiator (but not directly onto the radiator core) or header / expansion tank. K-Seal ULTIMATE will not be affected by any coolant, antifreeze or other additives already in the cooling system. It can be used in hot or cold engines.

3. Start your engine and get back on the road!

Once you have applied K-Seal ULTIMATE to your coolant system, simply run your engine as normal.

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 ULTIMATE

Expert Advice

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

Expert Advice

Where to buy K-Seal

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

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