The 8 Best Radiator Stop Leaks

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We spent 23 hours on research, videography, and editing, to review the top picks for this wiki. When smoke billows from the exhaust, the temperature rises, and the air smells too sweet, the likely culprit is an antifreeze leak. Because they're exposed to the elements, radiators are often the first component to corrode and start to expel fluid. One of these specially formulated sealers can stop your system from losing coolant until you can find a more permanent solution. When users buy our independently chosen editorial picks, we may earn commissions to support our work. Skip to the best radiator stop leak on Amazon.

8. AlumaSeal Powder

7. Irontite Ceramic

6. Liquid Aluminum

5. K-Seal HD

4. Liquid Glass Metallic

3. K-Seal Multi-Purpose

2. Bar's Concentrate

1. Bar's Tablets


Christopher Thomas
Last updated on May 04, 2018 by Christopher Thomas

Building PCs, remodeling, and cooking since he was young, quasi-renowned trumpeter Christopher Thomas traveled the USA performing at and organizing shows from an early age. His work experiences led him to open a catering company, eventually becoming a sous chef in several fine LA restaurants. He enjoys all sorts of barely necessary gadgets, specialty computing, cutting-edge video games, and modern social policy. He has given talks on debunking pseudoscience, the Dunning-Kruger effect, culinary technique, and traveling. After two decades of product and market research, Chris has a keen sense of what people want to know and how to explain it clearly. He delights in parsing complex subjects for anyone who will listen -- because teaching is the best way to ensure that you understand things yourself.


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