Updated: 26 Jun 2025

10 Best head gasket sealers of 2025

Explore up to 32% Off

Updated: 26 Jun 2025

#1

Best Choice

BlueDevil Products 38386 Head Gasket Sealer - 1 Quart

9.9

BlueDevil Products

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Main highlights

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.

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.

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.
#2

Best Value

Bar's Leaks HG-1 Head Seal Blown Head Gasket Repair

9.7

Bar's Leaks

-25%

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Main highlights

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.

REPAIR BLOWN HEAD & INTAKE GASKET LEAKS: The fastest, safest way to solve your vehicle’s coolant-related head gasket issues.

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.

-25%
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#3

Nulon PHGR-750 Permanent Head Gasket Repair 750 ml

9.4

Nulon

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Main highlights

Safe to use in all types of vehicles

Permanently seals head gasket leaks

Non-toxic and biodegradable
#4

BlueDevil Products 00209 Pour-N-Go Head Gasket Sealer - 16 Ounce

9.3

BlueDevil Products

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Main highlights

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.

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.

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.
#5

K-Seal Ultimate Head Gasket Repair to Permanently Fix Blown Head Gaskets, Cracked Heads & Blocks, Multicolor

9.0

K-Seal

-32%

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Main highlights

The ceramic micro-fibres in K-Seal Ultimate are carefully produced so that they will seal leaks up to 0.635mm in size

Permanently fixes blown Head gaskets, cracked heads and porous engine block

One bottle is enough to Fix gaskets in cars, SUVs and small trucks; large engines Require two bottles

-32%
#6

Steel Seal SSAMZ Head Gasket Repair

8.9

STEEL SEAL

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Main highlights

Steel Seal will work on all vehicles: cars, bikes, vans, pickups, 4x4s, tractors, lorries and boats.

Blown Head Gaskets

All Types of Head Gasket Failure
#7

K-Seal ST3501 Pour and Go Head Gasket Sealer, 16oz, Permanent Repair for Blown Head Gaskets, Cracked Heads and Blocks

8.7

K-Seal

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Main highlights

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

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

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
#8

Bar's Leaks Block Seal Head Gasket Sealant (Pack of 4),1100-4PK

8.6

Bar's Leaks

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Main highlights

REPAIRS INTAKE GASKET LEAKS: Works on gasoline engines, turbocharged engines, diesel engines, and heavy duty engines.

REPAIRS CRACKED HEADS & BLOCKS: Your vehicle is a good candidate for this product if it can idle for 20 minutes without overheating or having to add coolant.

REPAIRS BLOWN HEAD GASKETS: This product contains a blend of aramid and refractory fibers giving the strength of a bullet proof vest and the heat resistance of fire-proof clothing. As these particles penetrate a crack or the blown head gasket area, they lock together and bond forming a hard permanent ceramic type seal.
#9

Bars 1830976 H1S1L-27 Head Gasket 600ml

8.5

Bars

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Main highlights

Stops transmission fluid leaks

Stops leaks in manual transmissions and ensures gaskets and seals remain flexible.

Specially developed to restore worn seals and gaskets and stop leaks
#10

K-Seal K5501 Coolant Leak Repair Treatment for Antifreeze/Engine Coolant - Suitable for Car Engines, Water Pump Casing, Heater Core & Freeze Plug

8.3

K-Seal

-24%

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Main highlights

PERMANENT REPAIR: A permanent repair, guaranteed for the lifetime of the engine

FIXES MOST LEAKS: Fixes most leaks in water-cooled engines

EASY TO USE: Mixes with all types of anti-freeze + no draining or flushing

-24%