K-Seal Coolant Leak Repair	K-Seal Head Gasket Repair	K-Seal HD Coolant Leak Repair
Best Application For everyday coolant leaks in cars, motorcycles, and light trucks.	Best Application For head gasket leaks, cracked heads, and porous block problems.	Best Application For larger engines, HGVs, tractors, heavy plant, and commercial vehicles.
Shake, Pour & Go Easy one-step formula. Just shake, pour, and go. No draining or flushing needed.	Shake, Pour & Go Simple pour-and-go formula for head gasket and block repair.	Shake, Pour & Go Heavy-duty pour-and-go formula designed for larger cooling systems.
Seals Common Leaks Helps seal leaks in radiators, heater cores, water pumps, freeze plugs & blocks.	Seals Common Leaks Helps repair blown head gaskets, cracked heads, and porous blocks.	Seals Common Leaks Helps seal leaks in radiators, head gaskets, heater cores, water pumps & blocks.
Coolant Compatible Works with all types of antifreeze and coolant.	Coolant Compatible Works with all water-cooled engines and common coolant types.	Coolant Compatible Compatible with antifreeze and coolant systems in larger engines.
System Capacity 8 fl. oz. bottle treats cooling systems up to 20 quarts.	System Capacity 16 fl. oz. bottle for head gasket and block repair applications.	System Capacity 16 fl. oz. bottle treats larger cooling systems up to 60 quarts.

K-Seal Coolant Leak Repair

K-Seal Head Gasket Repair

K-Seal HD Coolant Leak Repair

Best Application

For everyday coolant leaks in cars, motorcycles, and light trucks.

Best Application

For head gasket leaks, cracked heads, and porous block problems.

Best Application

For larger engines, HGVs, tractors, heavy plant, and commercial vehicles.

Shake, Pour & Go

Easy one-step formula. Just shake, pour, and go. No draining or flushing needed.

Shake, Pour & Go

Simple pour-and-go formula for head gasket and block repair.

Shake, Pour & Go

Heavy-duty pour-and-go formula designed for larger cooling systems.

Seals Common Leaks

Helps seal leaks in radiators, heater cores, water pumps, freeze plugs & blocks.

Seals Common Leaks

Helps repair blown head gaskets, cracked heads, and porous blocks.

Seals Common Leaks

Helps seal leaks in radiators, head gaskets, heater cores, water pumps & blocks.

Coolant Compatible

Works with all types of antifreeze and coolant.

Coolant Compatible

Works with all water-cooled engines and common coolant types.

Coolant Compatible

Compatible with antifreeze and coolant systems in larger engines.

System Capacity

8 fl. oz. bottle treats cooling systems up to 20 quarts.

System Capacity

16 fl. oz. bottle for head gasket and block repair applications.

System Capacity

16 fl. oz. bottle treats larger cooling systems up to 60 quarts.

FIX IT FAST: Our advanced formula with 33% more sealing power than regular K-Seal, ensures a long-lasting, seal for challenging leaks. 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 seal leaks up to 0.64mm in size, without any adverse impact on the engine
VERSATILE COMPATIBILITY: Works with all types of coolant & compatible with a wide range of vehicle engine materials & heavy duty machinery.
Attention: If you notice bubbles coming from the radiator or coolant reservoir, or if K-Seal engine coolant stop leak is not sealing, the system might be over-pressurized. Refer to the Technical Specification section of this page for additional instructions to ensure a successful repair. Over 8 million bottles sold worldwide!

Contains: Zinc Gluconate, 4-Nonylphenol, Branched, Ethoxylated, Borax and Copper.

K-Seal ST3501 Pour & Go Head Gasket Sealer, 16 oz – Repairs Blown Head Gaskets, Cracked Heads & Engine Blocks