IRONTITE All Weather Coolant Leak Sealer — 16 oz Blue, In-System Radiator & Heater Core Sealant

IRONTITE All Weather Seal is a 16 oz blue, ready-to-use leak sealer that permanently seals minor to moderate cooling system leaks in radiators, heater cores, head gaskets, and hoses when the system reaches operating temperature.

Designed as a maintenance and repair aid for cars, trucks, and heavy equipment, IRONTITE All Weather Seal blends with antifreeze or coolant to form seals without gumming up passages. The formula is engineered to be compatible with a wide range of coolant types and common cooling system metals and plastics, delivering a low-risk way to stop leaks without disassembling the system.

How does IRONTITE All Weather Seal stop leaks while the engine runs?

The product contains reactive sealing particles that activate when the cooling system heats up and air contacts the leak site. That controlled activation allows the material to lodge into the leak path and harden into a lasting seal, minimizing coolant loss while maintaining flow throughout the system.

• Activates at normal operating temperature with heat and airflow
• Forms a durable seal that adheres to metal and plastic surfaces
• Works in-line—no disassembly required under most conditions

Will this damage my radiator, heater core, or clog the cooling system?

IRONTITE All Weather Seal is formulated to avoid creating sludge or obstructing heater cores and passages. When used as directed, it is safe for common materials in cooling systems and won’t cause the blockages associated with some stop-leak products.

• Non-sludging formula designed to maintain coolant flow
• Compatible with aluminum, cast iron, steel, and plastics
• Safe for use with traditional and modern coolant types

Which coolants and vehicles is this product compatible with?

The sealant mixes with conventional antifreeze/coolants, waterless antifreeze, and many proprietary formulations used in light-duty and heavy-duty vehicles. It’s suitable for passenger cars, fleet vehicles, commercial trucks, and some industrial equipment where a temporary or permanent in-system repair is needed.

• Works with ethylene- and propylene-glycol-based coolants
• Accepts waterless and specialty coolant systems
• Intended for a broad range of vehicle types and machinery

Who is this for? IRONTITE All Weather Seal is aimed at vehicle owners, fleet managers, and mechanics who need a fast, low-cost way to stop coolant leaks without immediate disassembly. It’s particularly useful as preventative maintenance or an emergency field repair for leaks in radiators, heater cores, head gaskets, hoses, and related cooling components. For large-scale or severe failures, use this as a temporary or diagnostic solution before pursuing full mechanical repair.