Permatex Plastic Tank Repair Kit — Clear 4" Crack & 0.375" Hole Repair, Fast-Curing Resin

Permatex Plastic Tank Repair Kit is a complete, ready-to-use system for repairing cracks up to 4" and holes up to 0.375" in non-fuel plastic tanks, delivering a durable fix in under an hour.

When a plastic reservoir, overflow bottle, or washer tank develops a leak, you need a reliable repair that’s quick and long-lasting without sending the part to a shop. This kit gathers every component required to make professional-looking repairs in minutes: a fast-curing resin formulated for plastic, clear instructions with photos, and the application tools to bond and seal the damaged area. It’s intended for commonly used automotive and marine plastic tanks (not for fuel tanks) and works best when applied in moderate temperatures.

How quickly will a repair set and be ready for use?

The Permatex resin is engineered to harden rapidly so you can return the vehicle or equipment to service the same day. Initial hardening occurs within 8–10 minutes, and the material reaches a functional cure in about 30 minutes under recommended conditions.

• Harden time: 8–10 minutes
• Functional cure: ~30 minutes
• Best working temperature: 50–75 °F for optimal cure

What sizes and types of damage can this kit fix?

This kit is built for common cracks and punctures found in plastic reservoirs and tanks. It can bridge and seal linear cracks up to 4 inches long and fill circular holes up to 0.375 inches in diameter, making it suitable for many small- to medium-sized leaks.

• Cracks: up to 4 inches in length
• Holes: up to 0.375 inch diameter
• Compatible with: washer reservoirs, coolant overflow tanks, water and waste tanks (not for plastic fuel tanks)

What comes inside the kit and what tools do I need?

The kit is designed to be turnkey: it includes the resin and the necessary application materials plus illustrated directions so you can complete the repair without extra supplies. For the best result, work on a clean, dry surface and follow the step-by-step photos.

• Includes resin formulated for plastic bonding and curing
• Contains application tools and photographic instructions
• No specialty equipment required—basic hand tools and cleaning supplies are all you’ll typically need

How durable is the repair and where should I not use it?

Repairs made with this Permatex kit are intended to be permanent for the types of plastic tanks specified. The cured resin provides a rigid, sealed patch that withstands typical operating conditions of reservoirs and overflow bottles. It should not be used on plastic fuel tanks or where manufacturer guidelines prohibit aftermarket repairs.

• Provides a permanent, hard cure suitable for many plastic reservoirs
• Not recommended for plastic fuel tanks or components exposed to incompatible chemicals
• Follow vehicle or equipment manufacturer instructions when in doubt

Who is this for: The Permatex Plastic Tank Repair Kit is ideal for DIYers, fleet technicians, and mechanics who need a fast, dependable solution for non-fuel plastic tank leaks—windshield washer reservoirs, radiator overflow bottles, coolant and water tanks, and similar containers. It’s particularly useful when a quick turnaround is required and replacing the tank immediately is impractical. If you need a field-ready, easy-to-follow repair that cures quickly and withstands normal service conditions, this kit is a practical choice.