LIQUI MOLY Radiator Stop Leak 3330 - Permanent Cooling System Seal

Purpose and Specifications

LIQUI MOLY Radiator Stop Leak (3330) is a fast-acting liquid sealant designed to permanently seal small leaks, hairline cracks, and porous solder joints in your vehicle's cooling system. One 150ml bottle treats up to 10 liters of coolant.

• Seals immediately: Works on stone chip damage, porous soldering points, and hairline cracks without clogging cooling lines
• Safe for all radiator types: Compatible with aluminum, plastic, and traditional radiators
• Works with all coolants: Compatible with standard coolants, antifreeze solutions, and cooling water additives
• No engine damage: Contains no harsh chemicals that harm water pumps or heating circuits
• Preventive use: Can be added to new cooling systems to protect against future leaks

When to Use / Replace?

Add this product when you notice coolant level dropping between services, or use preventively during routine maintenance. The sealant remains in your cooling system permanently—it does not degrade or require replacement. One application lasts the life of your vehicle's cooling system.

How to Apply

• Shake the bottle thoroughly before use
• Pour contents into the cold cooling system expansion tank
• Start the engine and turn on the heater
• Drive for at least 10 minutes at normal operating temperature
• Plastic particles in the formula accumulate at leak points and seal them permanently

Frequently Asked Questions

Q: Will this product block my cooling lines or cause clogs?
A: No. LIQUI MOLY Radiator Stop Leak is specifically formulated not to set, block channels, or cause secondary damage. The plastic particles only accumulate at actual leak points.

Q: Can I use this in older vehicles with traditional copper radiators?
A: Yes. This product is suitable for all cooling water and heating systems, including those with or without water filters, and works on aluminum, plastic, and traditional radiators.

Q: How long does it take to work?
A: The sealant begins working immediately once the coolant reaches operating temperature. After a 10-minute drive, small leaks are sealed and your cooling system functions normally again.