10 Best head gasket sealer (2025)

• REPAIR BLOWN HEAD & INTAKE GASKET LEAKS: The fastest, safest way to solve your vehicle’s coolant-related head gasket issues.
• SEAL WARPED / CRACKED HEADS & BLOCKS: Your vehicle is a good candidate for this solution if it can idle for 15 minutes without overheating or having to add coolant.
• ANTIFREEZE COMPATIBLE, NO FLUSHING REQUIRED: Use with ALL types of 50-50 mix coolant including yellow, orange, pink, red, blue and green silicate based & non-silicate based (OAT / HOAT) antifreeze, and water. No draining or thermostat removal required.
• REINFORCED WITH CARBON FIBERS: Works with ALL gasoline and diesel engines. This also for use in all racing applications.

• FIX IT FAST: Our multi-purpose solution works in minutes to quickly & permanently seal leaks in the radiator, head gasket, freeze plugs, block, heater matrix & water pump. Fixes most leaks in water-cooled engines
• STOP HOLES & CRACKS: With just 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
• EASY TO USE: K-Seal couldn't be simpler to use & requires no draining or flushing; just shake, pour & go - shake the bottle, add the fluid to your coolant system & run your engine as normal
• VERSATILE COMPATIBILITY: Compatible with all types of antifreeze coolant. Suitable for use in both cars & light trucks with up to 12 cylinders. A permanent repair for the lifetime of the engine
• PROFESSIONAL-GRADE RELIABILITY: Trusted by mechanics, our sealer delivers a durable & long-lasting repair. 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

• PERMANENT REPAIR: Our advanced formula with 33% more sealing power than regular K-Seal, ensures a long-lasting, permanent seal for challenging leaks. Permanently fixes blown head gaskets, cracked heads & porous engine blocks in cars
• STOP HOLES & CRACKS: With just 1 step our unique formula with ceramic micro-fibres, will permanently seal leaks up to 0.64mm in size, without any adverse impact on the engine
• EASY TO USE: It requires no draining or flushing; just shake, pour & go - shake the bottle, add the fluid wherever you top up your coolant & run your engine as normal. For larger engines (HGV's / Plant) use 2 bottles
• VERSATILE COMPATIBILITY: Works with all types of coolant & compatible with a wide range of vehicle engine materials & heavy duty machinery. A permanent fix for the lifetime of the engine
• PROFESSIONAL-GRADE RELIABILITY: Trusted by mechanics, our sealer treatment delivers a durable & long-lasting repair. A cost-effective head gasket & block repair, enhancing the performance of your vehicle’s cooling system. We've sold millions worldwide & are independently verified by university testing to meet ASTM D3147.

• Easy to use: The BlueDevil Head Gasket Sealer is designed to be easy to use, allowing you to quickly and easily seal leaks in your engine without the need for any special tools or skills.
• Permanent seal: This product is formulated to provide a permanent seal for your head gasket, ensuring that you won't have to worry about leaks or other issues down the line. It will repair and seal leaks in blown head gaskets, warped or cracked heads, heater cores, and freeze plugs.
• Compatible with all types of engines: Compatible with gasoline and diesel engines, making it a versatile product that can be used on a wide range of vehicles.
• Safe to use: Contains no solid or particulate matter and will not clog or harm your engine. It bonds to metal, aluminum, cast, alloy, or plastic, making it safe to use as a permanent seal for your head gasket leak

• Easy to use: Pour-N-Go, Do It Yourself formula is designed to be easy to use, allowing you to quickly and easily seal leaks in your engine without the need for any special tools or skills.
• Permanent seal: This product is formulated to provide a permanent seal for your head gasket, ensuring that you won't have to worry about leaks or other issues down the line. It will repair and seal leaks in blown head gaskets, warped or cracked heads, heater cores, and freeze plugs.
• Compatible with all types of engines: Compatible with gasoline and diesel engines, making it a versatile product that can be used on a wide range of vehicles.
• Safe to use: Contains no solid or particulate matter and will not clog or harm your engine. It bonds to metal, aluminum, cast, alloy, or plastic, making it safe to use as a permanent seal for your head gasket leak

• Stops block leaks
• Seals cracked cylinder heads and blocks
• Repairs blown head gaskets
• Dual Action 2 Part Formula — LIQUID CERAMIC: Liquid penetrates large and small leaks to form a seal actually harder than the original head gasket — REINFORCED FIBERS: Fiber additives lock together with liquid to increase strength and promote a permanent seal
• Head Gasket Sealant is NOT COMPATIBLE with antifreeze and must only be added to the cooling system after ALL ANTIFREEZE has been flushed and removed.

• SAFELY SEALS GASKET AND OTHER SEVERE LEAKS: One step formulation contains a combination of antifreeze compatible sodium silicate sealing liquid and various size gasket sealing particles which penetrate gaps and cracks then harden to permanently stop leaks. Heavy duty formula works on aluminum and cast iron heads & blocks, along with sealing all other engine cooling system leaks better than a traditional stop leak. This includes repairing head gaskets, cylinder heads, intake gaskets, cracked blocks and freeze plugs.
• QUICKLY AND PERMANENTLY STOPS COOLANT LEAKS: This works because of the extreme heat inside the combustion chamber (5000°F) that acts as a catalyst to permanently harden the material to make it stronger than the actual head gasket itself.
• ONE STEP - NO DRAINING REQUIRED - EASY TO USE: Your vehicle is a good candidate for this product if it can idle for 20 minutes without overheating or having to add coolant.
• USE WITH ALL TYPES OF TRADITIONAL OR EXTENDED LIFE COOLANT: Use with ALL types of traditional or extended life coolant including yellow, orange, pink, red, blue, purple and green silicate based & non-silicate based (OAT/HOAT) 50-50 mix antifreeze, and/or water.
• Made in the USA

This Steel Seal Blown Head Gasket Fix Repair Sealer - 8 Cylinder is a top choice in . Customers appreciate its quality, performance, and value.

• PERMANENT FIX: Seals larger holes with less fluid loss than competitive products to permanently repair leaks in 30 minutes or less.
• EASY TO USE: Our easy; pour-in formula allows you to fix leaks without having to drain your cooling system.
• PREMIUM FORMULA: Contains military strength fibers to create multi-layer repair over cracks with a web-like weave. Nanotechnology permanently fixes the smallest cracks and crevices. Lowers operating temperature as it circulates through cooling system.
• PRODUCT SPECIFICATIONS: CRC FiberLock Head Gasket & Block Repair is available in a 32 fl oz bottle.
• CRC INDUSTRIES: A market leader that offers impeccably designed chemical solutions to maintain; protect and repair different marine; heavy-duty motor vehicles; industrial-grade engines; household tools and electrical equipment.

This Steel Seal Blown Head Gasket Fix Repair Sealer - 6 Cylinder is a top choice in . Customers appreciate its quality, performance, and value.