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If you use ULTIMATE for a Head Gasket repair and it and it fails to fix the leak get in touch to find out about our money back guarantee. For all our other brands if you have a repair that subsequently fails contact us for a replacement bottle.
Reviews 493
Joe Lynch
Feb 09,2019This product is awesome! My stepson's car had a major antifreeze leak and was overheating. I thought more than likely head gasket or lower intake manifold gasket, both a very expensive fix. I have been told never to put an additive into the radiator as it could cause more problems and they do not work. Well against better judgment and looking at a large expense, I decided to try K-Seal. I followed the directions and the leak slowed down. I figured that I would try and add a second bottle because the leak was so bad and it had slowed down after the first bottle. Well after the second bottle it was completely sealed up and was not leaking at all. I would suggest this product to anyone without hesitation. It truly works! Thanks again
Donald Varner
Feb 06,2019I would like to start off by saying THANK-YOU. My vehicle is a 2006 KIA the tempter gage would read hot, but the vehicle would not feel over heating. At time I knew it was the Head Gasket. I was thinking I would have to spend a lot of money around thousand in repair or replace the vehicle being its over 13 years old. I purchased the sealant (1100) at a WalMart follow the direction and the vehicle is running great. It may last anything 13 years now. The Head Gasket Sealant (1100) is the best product there is. Thank-you. I was hoping the I can received any BAR'S advisement items you can spare I never see any for sale. Anything such as stickers, brochures, anything with the BAR'S logo. Once again Thank-you for your great product, That saved me a lot of money and time. Loyalty Customer for life. Donald
Mark Revels
Jan 31,2019Wow this product and customer service is simply the best. I've used other similar products in the past and they didn't work. So was a bit sceptical, I sent numerous emails to the company asking them many questions. All these emails and questions were answered quickly. Purchased the product and no more topping up the radiator reservoir every 4 days. Very Happy customer Look it's a no brainer, if the AA use this product it must work. Thank you K - Seal
Brett A. Curtas
Jan 11,2019I had classic symptoms of an emerging head gasket failure. I was recommended a competitors product which did not work. With nothing to lose I gambled on K-seal which was the only product to list actual sealing parameters. Within 3 minutes the exhaust vapor disappeared and coolant temperature completely stabilized. The engine has about 4 hours since then with 0 issues. Time will tell as to how permanent "permanent" really is but if it let go tomorrow it was still money well spent. An amazing product!!
Philip goldsmith.
Jan 10,2019Hi, my vauxhall meriva was overheating and the garage did a test on gasket and said it turned a yellow colour so used k-seal, hasnt overheated for a week.just wondered if it really is permanant.( fingers crossed)
Neil Osborne
Jan 05,2019Tried kseal today. It didn't work. Money back form online doesn't work either.!!!!
Harry Love Jr.
Jan 01,2019THANK YOU... GOD BLESS K SEAL.... AND THE TEAM OF PEOPLE BEHIND THIS PRODUCT!... #HeaterCoreFixed!!
James T. Dempster
Dec 31,2018Took my garage-kept 2003 Ford Taurus to local tire/maintenance shop with what I though to be a lower hose leak at the front of the engine. Pressure test revealed a pinhole leak in the water pump housing. The mechanic recommended K-Seal as a first step before the $700+ cost of replacing housing, gasket and water pump. I followed simple directions on the package and voila — problem solved.
Carl Thompson
Dec 30,2018Quoted £1050 to repair the head gasket on my 2010 insignia, test found exhaust fumes in the coolent. Was going through rediculous amounts of water and over heating at times. One bottle of k-seal ultimate, let it idle and heat and cool 3 times and magic, not loosing any water or over heating, I had the car booked in for repairs next week but thought I'd give k-seal a try first, what a result! AMAZED
Pete Turner
Dec 30,2018Hi my name is Pete I had a leaking water pump or bad gasket on my 2000 Honda Accord and used this product and within 5 min it stop and I was losing a half gallon of coolant only driving 12 miles to work all I can say is that this stuff really works I’m amazed and I’m a 16 year ASE mechanic and I stand behind this product I will be recommending in the future to help my customers out that just don’t quite have the money again thanks Kseal
kim lewis
Dec 30,2018I have a 2008 Saab 9-3 2.0... I had a major coolant leak.. I changed my houses just to find out I needed a water pump... I tried the k seal and it worked... Its been a little over 3 weeks and no leak... I am extremely happy..
ashley isom
Dec 21,2018Got because my transmission had a little pin hole..well needless to say it completly made it worse and i was stranded on the side of the road with my 2 year old.
David Howard
Dec 20,2018I.lost a lot of water in my ford focus i put the kseal in with water its been ok since realy good stuff
John Brown
Dec 18,20182003 Astra had a really bad leak bottom left hand corner I thought the leak was too bad but was worth a try as it was only £9.99 poured K-Seal in leak kept going but eventually leak stopped brilliant stuff old Astra lives for another day (leak was on the radiator)
Michael M
Dec 18,2018Tried this product on a Mazda radiator with a fairly slow coolant leak - slow drips of about a total of 250-500ml over the course of a day with travel of about 60km per day. It did initially slow the leak a little but only lasted about 3-4 days before returning to the same rate of leak. I had to get the radiator replaced to solve the coolant loss.
alex Randall
Dec 16,2018followed the instructions to the letter on my 07 audi a3, after adding this to the header tank the car became significantly worse and was loosing water even quicker than before. i fear it has blocked something it shouldn't of and im looking at scraping the car realistically. there is no cheap fix for guys
t edwards
Dec 01,2018My Mini Cooper s was diagnosed with a blown head gasket not wanting to spend£1k plus or lie on the drive doing it myself in the cold I tried a bottle of k seal . Put it in the header tank let it tick over for 25 minutes to warm up and then did a little road test- the temperature gauge stayed normal . To say I'm happy is an understatement thanks all at Kseal
Douglas Hipp
Nov 23,2018Have a 2004 VW Jetta 1.8t with a small coolant leak on cylinder 3 causing a misfire so after reading the reviews I decided to give it a try .. and after 3 heat cycles and making sure I did it right I still have the leak in the head gaskett sigh. I wasn't hoping for a merical but after the reading all the positive reviews I was hoping for the best so I hate to be that guy but this did not work for me so now it's head gasket time. If any ideas my email is doug Hipp Jr @ Hotmail com ... Without the spaces
CDT2018
Nov 21,2018I’m a single parent student who works part time. Recently purchased a 2004 Punto to enable me to work.. the car started to overheat and lost heat from inside the cabin.. took it to a garage who informed me it was a head gasket issue and quoted £557 to fix. There was no way I could possibly afford it and given id only paid just over that for the car, I was about ready to scrap it and looking at the prospect of having no work for the foreseeable until my partner suggested this product and it worked like a dream!! Thank you so much! This product has seriously saved my skin.. and hopefully my car! Absolute genius product
Boyd Griffin
Feb 11,2019This is the story of spending less than $25.00 to fix a head gasket problem rather than paying over $4,600.00 through the dealership. What a miracle! Thank you. Over a year ago my 2012 Prius V started to have a cold soak issue on start up. It was an intermittent problem at the time, (once in a couple of weeks) and the car would rattle on startup. The dealership said they could not diagnose the problem unless it could be duplicated. About 6 months ago the check engine light came on and the car was then diagnosed as a misfire on one of the cylinders. Changing the igniter and the spark plug did not solve the problem. It continued to get worse and the Dealership was able to diagnose the problem as a head gasket issue where coolant was being pushed into the cylinder that was causing the misfiring. The problem was now fairly regular. Since my job was a rideshare driver for Lyft and Uber with food deliveries for Peach, and I averaged about 1,000 miles per week, it was very important to get my car running correctly again, It had 213,000 miles on the engine but because the car is not paid off yet, the hybrid battery was replaced less than 6 months earlier and since these cars can go over 300,000 miles it was important to get the problem fixed and continue to drive this car. The dealership quoted over $4,600.00 to replace the head gasket. I di quite a bit of research and some of the other products for sealing a head gasket leak had reviews of how radiators and water pumps, etc. went bad after using their product so I was very nervous about potentially making the problem worse. I was looking at possibly getting a used engine with low miles but I also knew from research that the head gasket leak is a known issue on this car. After researching I first put in GM Cooling System Seal tablets because they had a very high rating on Amazon and GM uses them in their assembly lines so they should be safe. The tablets helped out but did not completely correct the problem. There was still white smoke from the exhaust but the coolant was just barely leaking and the check engine light went off. Next, I ordered the K-Seal ST5501 and followed the directions. The white smoke stopped completely in just a few hours of driving and the reserve tank for the coolant is not losing any fluid. For now, at least, it seems as if the problem is fixed. I will report back after some time has passed with an update. Including the cost for the Cooling System Seal Tablets the total cost was under $25.00. If I were to do this over again I would skip the Seal Tablets and just put in the K-Seal to see if that would fix the problem. As a suggestion for someone else with a Prius that might be considering this, after putting the K-Seal in the coolant reservoir, I put the Prius into "Inspection Mode" because this makes the car engine run constantly until it is taken out of "Inspection Mode". You do not want to drive the car during this time as it is only for idling and driving the car in inspection mode could damage it. I let the car idle for 30 minutes before shutting off the engine and then starting it up again which puts it into the regular driving mode. You can search online for the method to put your car into this mode which involves pressing the start button and combinations of applying the gas pedal and brakes.