Can be manually applied, allowing for straightforward operation. Resists rust and corrosion for lasting use. Requires only up 20 minutes to seal spilling.

Cons

May not be as well quality as the liquid version.

J-B Weld

Perm-O-Seal Radiator Stop Leak

Heavy-Duty Choice

This is a durable heater sealant that offers long-lasting protection, making it an excellent choice for tougher leaking.

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Heavy-Duty Choice

Bottom Line

This is a durable heater sealant that offers long-lasting protection, making it an excellent choice for tougher leaking.

Pros

Non-toxic formula. Goes directly into cooling system to fix spilling. Long-lasting. Prevents rust from interfering with internals. Versatile application for most heater types.

Cons

Can work fast, which may make it difficult to use.

AlumAseal

ASBPl12 Radiator Stop Leak

Versatile Application

From cooling systems to heater spilling, this sealant can be used in a range of seasons and temperatures.

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Versatile Application

Bottom Line

From cooling systems to heater spilling, this sealant can be used in a range of seasons and temperatures.

Pros

Quick-drying seal. Safely applies on metal, plastic, and rubber. Can be added with other coolants. Lubricates water pump for safer flow.

Cons

Small package may not be the best choice for more serious spilling.

Prestone

AS145 Radiator Sealer Stop Leak

Purposeful Formula

Through the composition of high-quality ingredients, this formula seals spilling and other damages within heaters.

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Purposeful Formula

Bottom Line

Through the composition of high-quality ingredients, this formula seals spilling and other damages within heaters.

Pros

Professionally-designed option stops damages in water pumps and heaters. A good option for larger spilling. Stops damage and harmful containments.

Cons

Confusing to use, especially for those with less experience.

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First Reviewed

September 25, 2021

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