Bars Leaks 1109 Liquid Copper Block Seal, Intake and Radiator Stop Leak, 18 oz. | One Step, Safe for All Cooling Systems

**** The Bars Leaks 1109 Block Seal Liquid Copper is a highly debated product amongst car enthusiasts and everyday drivers dealing with cooling system leaks. Many customers have found success with this sealant, noting its cost-effectiveness relative to the expense of repairs or replacements. A significant number of users reported that it effectively fixed leaks in their vehicles, particularly in older models, with users praising its ability to seal severe leaks in the radiator and timing cover. However, responses to the product are mixed; while some users shared positive experiences showing how quickly the product acted to stop leaks, others expressed caution and outlined negative experiences. Several customers mentioned potential issues with clogging, warning that improper use or following inaccurate procedures led to complications in their cooling systems, including overheating situations. Those that successfully used the Bars Leaks 1109 highlighted the importance of following the instructions carefully, particularly regarding the use of antifreeze and allowing the engine to run after application. Other users advised against rushing into using the product without diagnosing the true cause of the leak, suggesting that alternatives to sealants, like replacing damaged components, might be more beneficial in some cases. Overall, the Bars Leaks 1109 appears to be a viable stopgap measure for minor leaks but comes with important caveats regarding proper application and potential risks of clogging. **