Permatex Copper Spray-A-Gasket Hi-Temp Adhesive Sealant - Heat

In this review of the Permatex Copper Spray-A-Gasket Hi-Temp Adhesive Sealant the bottom line is simple: this aerosol sealant is aimed at mechanics and home wrenchers who need a durable, heat-resistant gasket solution. It earns a recommendation for jobs where metal-to-metal contact runs hot and a forming chemical gasket is impractical. The reviewer found the product's main advantage is its metallic copper formula that helps dissipate heat and resist gasoline and other automotive fluids while creating a reliable, instant seal on rough or imperfect surfaces.

Key Features

• Fast drying: Dries quickly to form a tacky, adhesive seal that reduces downtime during engine work.
• High temperature range: Operates from -50F to 500F so it withstands exhaust manifold and cylinder head heat without breaking down.
• Metallic copper finish: The copper formulation helps dissipate heat and can improve heat transfer across the sealed surface.
• Fluid resistant: Resists all types of automotive fluids, especially gasoline, so seals remain intact in fuel-exposed areas.
• Fills imperfections: The spray fills hot spots and minor surface irregularities for an instant, uniform seal on gaskets and flanges.
• Convenient packaging: Comes in aerosol cans for targeted application and easier coverage of awkward surfaces.

Who It's For

This product is best for professional mechanics, performance tuners, and DIY enthusiasts who work on cylinder head gaskets, exhaust manifold gaskets, carburetor gaskets, or other high temperature engine joints. Its ability to resist gasoline and maintain adhesion under heat makes it useful for both import and domestic vehicles where a formed chemical gasket cannot be used.

It is less appropriate for non-automotive low-temperature sealing tasks or for users who require a flexible, long-term elastomeric gasket material for vibration-prone applications; such users should consider other gasket types designed for constant flex and movement.

Pros & Cons

Pros

• Strong adhesion that holds up under high heat and pressure for engine applications.
• Excellent resistance to automotive fluids, making it suitable for gasoline-exposed areas.
• Helps dissipate heat and fills surface imperfections to prevent gasket burnout.

Cons

• Spray quality receives mixed feedback, so users may find application control varies between cans.

Specifications

Brand	Permatex
Package size	Pack of 12 aerosol cans
Can volume	12 oz. aerosol can (9 oz. net wt.)
Temperature range	-50F to 500F
Primary use	Hi-temp adhesive gasket sealant for engine applications
Fluid resistance	Resists gasoline and other automotive fluids

Our Verdict

The Permatex Copper Spray-A-Gasket Hi-Temp Adhesive Sealant is a practical choice for anyone sealing high-temperature engine joints where heat dissipation and fluid resistance matter. It provides solid adhesion and durability at a reasonable value for mechanics and experienced DIYers, though users should allow for some variability in spray control between cans.

Frequently Asked Questions

Can this sealant handle exhaust manifold temperatures?
Yes. The product is rated to 500F and is intended for exhaust manifold and similar high-temperature applications.

Will it resist gasoline and engine fluids?
Yes. The copper formula resists all types of automotive fluids, especially gasoline, so it holds up in fuel-exposed areas.

Is this a replacement for a formed gasket?
It is intended for situations where a chemical gasket is not an option; it seals minor imperfections but is not a direct substitute for some engineered multi-layer gaskets in all cases.