Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.)
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Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.)

Part No. PLT11 Warranty Details  
Seal internal, external and coolant-to-oil leaks with Bar's Leaks Stop Leak Heavy-Duty Radiator Sealer. The pelletized formula works safely on plastic, aluminum and metal radiators. Product Features: Designed for use on plastic, aluminum and metal radiators, heater cores, blocks, heads, gaskets and freeze plugs, Compatible with conventional green (silicate-based) and red, orange or yellow (OAT) antifreeze, Patented Rhizex pellets dissolve quickly to seal internal, external and coolant-to-oil leaks, Lubricates water pump seals and prevents formation of rust and scale, Helps to prevent corrosion and control electrolysis, 1 bottle treats systems up to 4 gallons

Product Features:
  • Protects Engine Cooling Systems
  • Stops Current and Future Leaks
  • In hibits Rust & Corrosion
  • Lubricates Water Pump Seal
  • Helps Control Electrolysis
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Antifreeze Type Compatibility:Yes
Boiling Point at 50/50 Mixture:>480 deg F
Contains Corrosion Inhibitors:No
Contains Ethylene Glycol:No
Contains Lubricant:No
Contains Stop Leak:Yes
Manufacturer Warranty Compatibility:Yes
Non-Toxic:Yes
Radiator Material Compatibility:All
Recommended Change Interval:12000 mi

REVIEW SNAPSHOT®

by PowerReviews
Bars LeakStop Leak Heavy-Duty Radiator Sealer (11 fl. oz.)
 
3.1

(based on 13 reviews)

Ratings Distribution

  • 5 Stars

     

    (5)

  • 4 Stars

     

    (1)

  • 3 Stars

     

    (2)

  • 2 Stars

     

    (0)

  • 1 Stars

     

    (5)

58%

of respondents would recommend this to a friend.

Pros

  • Easy to use (10)
  • Reliable (4)

Cons

    Best Uses

    • Home garage (5)
    • Upkeep (5)
    • Roadside repairs (4)
      • Reviewer Profile:
      • Auto enthusiast (4), Casual driver (4), Mechanic (4)

    Most Liked Positive Review

     

    Used by new car manufactures for decades

    Bars stop leak has been used in new cars for decades. It was put in every older Cadillac everytime a radiator was replaced by GM service centers nation wide due to their systems having...Read complete review

    Bars stop leak has been used in new cars for decades. It was put in every older Cadillac everytime a radiator was replaced by GM service centers nation wide due to their systems having leaks. Mainly intake leaks on HT-4100 series. Its a great product and I have added it to hundreds of vehicles for over 35yrs without any issues.
    I have used it on some really bad leaks that I though it would be a waste of money by adding it and ended up being simply amazed it worked on them. Not just that it stopped it fast as much as it stopped them for good. Really great product and just so glad Prestone didnt change it after buying Bars years ago.

    VS

    Most Liked Negative Review

     

    bad stuff

    dont use it,it will stop up your radiator and cause over heating and you will have to get another radiator!!!!!

    dont use it,it will stop up your radiator and cause over heating and you will have to get another radiator!!!!!

    Reviewed by 13 customers

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    Displaying reviews 1-10

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    5.0

    Used by new car manufactures for decades

    By KC

    from USA

    About Me Auto Enthusiast, Mechanic

    Verified Buyer
    3 or more reviews submitted

    Pros

    • Can Withstand Use
    • Easy To Use
    • Only One To Use
    • Reliable

    Cons

      Best Uses

      • Automotive Repair Shop
      • Conditions System
      • Prevents Future Repairs
      • Roadside Repairs
      • Upkeep

      Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

      Bars stop leak has been used in new cars for decades. It was put in every older Cadillac everytime a radiator was replaced by GM service centers nation wide due to their systems having leaks. Mainly intake leaks on HT-4100 series. Its a great product and I have added it to hundreds of vehicles for over 35yrs without any issues.
      I have used it on some really bad leaks that I though it would be a waste of money by adding it and ended up being simply amazed it worked on them. Not just that it stopped it fast as much as it stopped them for good. Really great product and just so glad Prestone didnt change it after buying Bars years ago.

      Comment on this review(earn points)

       
      5.0

      worked great Cadillac north star

      By william

      from folkston ga

      About Me Casual Driver

      Pros

      • Easy To Use

      Cons

        Best Uses

        • Upkeep

        Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

        Need pellets for north star 4.6 used this product an it worked great to replace the gm pellets for cooling systen

        Comment on this review(earn points)

        (1 of 1 customers found this review helpful)

         
        5.0

        Bar's stop leak

        By donrm

        from Westchester,Ohio

        About Me Auto Enthusiast, Truck Enthusiast

        Verified Buyer
        Level 1

        Pros

        • Easy To Use
        • Reliable
        • Saved Me 200

        Cons

          Best Uses

          • Automotive Repair Shop
          • Home Garage
          • Roadside Repairs

          Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

          I have a Ford F600 Dump truck. The power steering belt came off & trashed the radiator, so I thought. I checked prices on a new radiator. Up and more than $200. I thught I would try the Bar,s stpo leak, had great reviews. I had a few squirters on my radiator. 1 bottle & NO LEAKS.Saved me more than $200 BUCKS!!!!!!

          Comment on this review(earn points)

           
          5.0

          Good Stuff

          By 2002 Cadillac Deville

          from Griffin, GA

          Verified Buyer
          3 or more reviews submitted

          Pros

          • Easy To Use
          • Reliable

          Cons

            Best Uses

            • Roadside Repairs
            • Upkeep

            Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

            Just follow the instructions folks. It's not a miracle worker but I once drove an Oldsmobile around for 5 years with cracked heads (not the gasket, the heads) and one bottle a year helped me to wait till I could fix it right. Steamy windows due to weepy heater core - very likely to put an end to that problem. Small hole in your radiator or radiator end caps - very likely to put an end to that too. In fact, if the mandrel in your water pump is a little leaky or some freeze plugs have pin hole and you need some time, I would bet this will help. Just be sure to follow the instructions.

            Comment on this review(earn points)

            (1 of 2 customers found this review helpful)

             
            1.0

            Didn't Help, Might've Made Leak Worse

            By StevenCee

            from Atlanta, GA

            About Me Casual Driver

            Verified Buyer
            Level 2

            Pros

            • Easy To Use

            Cons

            • Didn't work
            • May Worsen The Leak

            Best Uses

              Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

              I used it as directed, and within a few days noticed my coolant leaking on the ground, when I parked. I could see it dripping down, and kept having to put more coolant into the car, to maintain proper levels. When I took it to a garage, they showed me a hariline crack on the top of the radiator. I discovered that my mechanic had mentioned it to me months ago, but I forgot he did, and since I only had to add fluid now & then, didn't think it was a pressing issue. That's when I tried the Stop Leak, thinking it might stop up my slow leak. Well, as I said, if anything, it made it much worse. Now I have to get a new radiator...

              Comment on this review(earn points)

               
              3.0

              Not a fix just for maintenance

              By RC

              from N PLF NJ

              About Me Mechanic

              Verified Buyer
              Level 2

              Pros

              • Easy To Use

              Cons

                Best Uses

                • Upkeep

                Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

                easy to use just didnt fix 2 little pinholes had to drain rad and remove to have pro fix

                Comment on this review(earn points)

                 
                5.0

                I would buy again

                By ranger

                from manchester,n.j

                About Me Casual Driver, Mechanic, Truck Enthusiast

                Verified Buyer
                3 or more reviews submitted

                Pros

                • Can Withstand Use
                • Compact Design
                • Easy To Use
                • Reliable

                Cons

                  Best Uses

                  • Home Garage
                  • Upkeep

                  Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

                  Tryed other products,they did not work as well as this brand

                  Comment on this review(earn points)

                  (4 of 8 customers found this review helpful)

                   
                  4.0

                  Stops most leaks it seems

                  By Backyard Junk Mechanic

                  from Central Virginia

                  About Me Auto Enthusiast

                  Verified Buyer
                  Helpful Reviewer

                  Pros

                  • Easy To Use

                  Cons

                    Best Uses

                    • Home Garage

                    Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

                    First time I have used this product in years, and it still works. The pellets seem to melt and fill in any leaks in the radiator and heater coil. I had a leak in my heater coil and it has stopped, although the smell is still sometimes present when heat is cut on.
                    ***Don't know if it is related, but a heater hose bursted the day after I put this product in the vehicle's radiator, but it was an easy fix.***

                    Comment on this review(earn points)

                    (4 of 8 customers found this review helpful)

                     
                    1.0

                    Don't use this stuff

                    By BeN

                    from OKC, Oklahoma

                    About Me Casual Driver

                    Pros

                      Cons

                      • Difficult To Use

                      Best Uses

                        Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

                        Used this junk, and my car is still at the repair shop. Coolant can't circulate because this stuff has clogged the motor even with a new radiator. It will be cheaper to get a new radiator, than to buy this

                        Comment on this review(earn points)

                        (4 of 8 customers found this review helpful)

                         
                        1.0

                        Sludgy and Sandy

                        By blitz

                        from winterville, nc

                        About Me Auto Enthusiast, Competitive Driver, Mechanic

                        Pros

                          Cons

                            Best Uses

                            • Home Garage

                            Comments about Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.):

                            Well when i had my old radiator with a leak i used this and it did seal up the leaks when i first used it but then it leaked again few days later. And when I flushed system out and installed a new radiator month or so later, the overflow tank was turning black so i keep dumping the coolant from it and refilling it but it kept turning black. So I Opened radiator cap and there was like black sludge on top and it wsa sandy like someone pour some sand into radiator. I would never use this again instead I would just replace things and keep it maintained

                            Comment on this review(earn points)

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                            Do you have questions about this product?(earn points for answers!)

                             

                            Ask a question, get answers from real customers and in-house experts. Or contact Customer Care by email or call 1-877-238-2623.

                            7 Questions | 7 Answers
                            Displaying questions 1-7
                            • Q:

                              do i add this to radiator when it is hot or cold?
                              Asked on 11/22/2014 by csak from lorton, va

                              1 answer

                              • CUSTOMER CARE

                                A:

                                Hi CSAK, glad to assist you! Here is the direction to use this product. Cooling systems that are dirty or partially clogged should be flushed before usage. First, allow engine to cool so radiator cap can be safely removed and shake well to pour directly into radiator. Do not pack pellets in radiator. Pellets may be pre-dissolved if necessary by putting them in hot water. Note: If you don’t have access to radiator, remove top hose where it connects to top of radiator and install product in hose. Reattach hose and tighten clamp. Fill radiator and overflow tank to proper level, reinstall radiator cap and drive or idle engine for 15 to 30 minutes. Leave Bar’s Leaks in cooling system for preventative maintenance. Use once a year to help guard against future leaks. For more information please visit this link. URL - http://barsproducts.com/system/pdfs/64/original/PLT11%20Tech%20Sheet.pdf?1377268505

                                Answered on 11/24/2014 by Steve from AAP
                            • Q:

                              How far can I go with out it starting to leak again? Will it last for a 3- 3 1/2 drive?
                              Asked on 7/10/2013 by Missy from Milwaukee, Wi

                              1 answer

                              • CUSTOMER CARE

                                A:

                                The recommended change interval for the Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.) (Part No. PLT11) is 12000 miles. For any further assistance, please feel free to call us at: 1-877-238-2623 or visit the nearest Advance Auto Parts store and one of our Parts Pros will gladly assist you with any questions or concerns you may have.

                                Answered on 7/11/2013 by Steve from AAP
                            • Q:

                              Will this product clog up and/or otherwise harm the cooling system and/or cause the engine and/or transmission to overheat?
                              Asked on 6/11/2013 by Hank from Jacksonville, Fl

                              1 answer

                              • CUSTOMER CARE

                                A:

                                No, this Bars Leak Stop Leak Heavy-Duty Radiator Sealer (11 fl. oz.) -part# PLT11 will not harm the cooling system and cause the engine and transmission to overheat as it is to protect the Engine Cooling Systems. For any further assistance, please feel free to call us at: 1-877-238-2623 or visit the nearest Advance Auto Parts store and one of our Parts Pros will gladly assist you with any questions or concerns you may have.

                                Answered on 6/11/2013 by Vincent from AAP
                            • Q:

                              can i use this on a jimmy? it takes dexcool coolant
                              Asked on 8/30/2011 by sweetzz from Mi

                              1 answer

                              • CUSTOMER CARE

                                A:

                                Yes, you should be able to use this in your Jimmy.

                                Answered on 8/30/2011 by Steve from AAP
                            • Q:

                              I have a 48 Willis Jeep that the radiator is leaking along a seam were it is sealed togeather. It may be a copper radiator. Will this work
                              Asked on 8/25/2011 by Anonymous

                              1 answer

                              • CUSTOMER CARE

                                A:

                                It will work only on plastic, aluminum and metal radiators.

                                Answered on 8/25/2011 by DIY Daniel from AAP
                            • Q:

                              will it work on a plastic radiator
                              Asked on 7/6/2011 by Lynnbird from North Little,,AR

                              1 answer

                              • CUSTOMER CARE

                                A:

                                Yes, this should work fine on a plastic radiator.

                                Answered on 7/7/2011 by Vincent from AAP
                            • Q:

                              can this perminately stop a leak?
                              Asked on 2/3/2011 by rick from new enterprise pa

                              1 answer

                              • CUSTOMER CARE

                                A:

                                Yes, this Bars Leak Stop sealer stops leak permanently.

                                Answered on 5/11/2011 by Just Ask Jacob! from AAP
                            Displaying questions 1-7

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