K-Seal ST5516 Heavy-Duty Multi-Purpose One Step Permanent Coolant Leak Repair, 16 oz, Pour and Go, Mixes with All Antifreeze, No Flushing Required

Over the Decades, I've had to make use of a "stop leak" of one form or another.... some work, and others...not so much. I had need to try and at least temporarily... seal up a drip coming from a "new" water pump on my LB7 Duramax powered GMC Sierra 2500HD... about TWO years ago. I found this "K-Seal"..... all I can say is, READ and FOLLOW the specific directions..... and you Will be a "happy camper"!! This stuff Really Works!! If your even thinking about having an engine fluid sealer on hand... just in case, then look no further... this "K-SEAL" truly Does work.

This stuff really works! Had a little Kia Rio that was overheating and misfiring. Found water in the oil when I pulled the dipstick. Ran this through the engine and within an hour it sealed the head gasket and the car is running great now. No more overheating or misfiring at all.

Used it on my 2004 malibu.I used half a bottle.Works great !!! I was shocked.The Car had water squirting out of the tail pipe every time you revved the motor...like alot.I shook it up and poured have into an empty water bottle then poured it into the hose that goes to the overflow. I didn't drain the antifreeze.It worked so fast I didn't belive it...But the car only has 78,000 or so miles so it shouldn't have had any problems that soon.So maybe the hole was small.Either way I'm super happy.3 weeks later it's still going.Oh yeah. And 3 weeks ago I failed my visual inspection while getting it smogged.I'll update ones I take it back.

Works great

After reading many reviews, this product was used on several f250's like mine with similar water leaks. Mind blown that it fixed my leak in minutes when for days and many new Ford parts purchased, 20 bucks fixed it! Get it works! Oh and Ford make products old school and straight forward repair instead of tight spaces, and multiple clips and hoses!

it doesn't work, waste of money EDIT: DO NOT BUY THIS PRODUCT!!! IT CLOGS UP YOUR ENGINE AND WILL CAUSE IT TO BLOW UP!!!

Had a decent radiator drip on my RV. It is a huge radiator, 4 feet wide. I was going to get the radiator removed and fixed at a radiator repair place but it was so large I couldn't get it out of the bottom of the RV without jacking it up 2 feet.I was skeptical to try this K-Seal but the advertising said it could handle the heavy duty capacity of my 15 liter Cummins ISX diesel size, so I tried it.Within 25 minutes the leak was gone, pretty amazing. I let it run for an hour just to be sure. I will be driving it to a race soon and make sure it stays fixed.Happy that I didn't have to remove radiator, saved myself 10 hours of labor and hundreds of dollars to repair.

This works!!! i have a 2001 subaru that had a massive coolant leak somewhere. I poured this bottle and boom, never leaked again.