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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
Joanne Kiss
Dec 04,2019I used k seal as I was leaking coolant at a rapid rate, it did work for 8 days then started to leak again. I paid £10 for a bottle of this. Was hoping the repair would have lasted longer as it says on the tin! A little dissapointed to say the least....
Ataur Rahman
Dec 02,2019I have a Vauxhall Insignia (2.0 ltr Diesel), and half the coolants would go within a day or two. I used Kseal and it stopped for a couple of days, however, it's started to leak again. It is leaking a lot less, thinking maybe I should've used 2 bottles instead of one. So 3 stars as it didn't fix the leak but it has slowed the leak down.
Terry Hughes
Dec 01,2019In spite of my better judgement i used this product exactly as per the directions and taking great care to ensure there was no air in the system. The product did not stop my slow leak but it did block my heater core and partially blocked my radiator. There are products on the market that will get you by until you have time for proper repairs, this is not one of them. Not only do I still need to do those repairs but I will need to replace my heater core and radiator, provided I actually make it home to do so I fully expected the below generic reply. I will ask what are these many causes of a blocked heater core and partially blocked radiator AFTER using this product? When I finally limp my vehicle the 400km to my workshop I strongly suspect what i will find
Patrick Raymer
Nov 27,2019Giving it 3stars for now as only been 4days!! Been seems to of helped massively!! Have an a4 convertible and was topping up the coolant every 2 days due to head gasket failure so far no top up needed, car now starts first turn where as before took several attempts!! I understand this isn't a permanent solution and in the new year I'll be having the head done but for now thumbs up
jo blogs
Nov 27,2019Had coolant leak, no external sign on the ground.So used k.seal ok for about 3 weeks then I notes my temperature gauge was not woking the next day,The top hose blow,and bolild over.AA said posable head gasket.do you think second would help thanks. frederick stacey.
Melwin Rodrigues
Nov 26,2019If there were more stars would rate it more . It just saved my car and my wallet. Had leak on intake manifold was so worried when I read the review about this K seal I still had some doubts about its results , but I was wrong to doubt it. I just added it on my coolant tank and within 4 to 5 mins the leak was as getting lesser and finally stopped. So very much happy about it.Thank you so much whoever invented it , it’s really a big relief. Thankyou A++++++++++++++++++++++.
Kevin Kiper
Nov 23,2019My beloved 2006 Jaguar X-Type with just 75K miles recently developed a coolant to cylinder leak. My mechanic suggested that we try K-Seal. I'm really glad that we did. Fixed the leak immediately. Confirmed the fix with a combustion gas test. It's only been a week since the repair, but car is running great with no coolant loss. This is a fantastic product and I would not hesitate to recommended it to others, I would also add that the customer service team at K-Seal is first rate. They're very responsive to any questions you may have. I also give K-Seal high marks for their honesty. The product does not work on every type of leak, and they are very up front about that. I was fortunate that it does work well on coolant to cylinder leaks. Thanks again, K-Seal!!
Mark
Nov 23,2019I had a minor drip leak (only leaking when the vehicle was stopped). I put in one bottle (it is a 3.5L 6Cyl, unsure if 2 bottles were needed) and it did slow the leak, which I am grateful for, however it still seems to be leaking green coolant. Should I have put in 2 bottles as opposed to 1?
Mike Morris
Nov 22,2019For me this stuff has worked. My engine had a small leak which would. Let air into the system while the engine cooled. It wouldn't use. Oolant just not let it bring back from the expansion tank for the radiator. Dident happen straight away as it claimed but after 2 weeks the overflow started emptying. Have been checking this on and off for a week now and it's still working. So pleased
John Hardin
Nov 15,2019I was about to throw in the towel on repairing my wife's 1999 Ford Taurus with 180k miles as a head gasket leak had finally taken its toll and the cost for a teardown repair exceeded the vehicles value even though I could do the job myself. I had used sealer additives in the past for copper radiator leaks with success and via a web search came across K-Seal. I bought the 8oz bottle and added it to the upper radiator hose. After a short drive I went back to the barn and after the car cooled I opened the coolant reservoir and to my surprise it was still at the full level with some particles of the K-Seal visible. In the past the reservoir would have been empty by now and moisture coming out the tail pipe. The cylinder that had a miss with a CEL code cleared and the car now idles and runs smoothly. Awesome stuff!
Michael Farace
Nov 13,20192001 Cadillac Eldorado Can you tell me if K-Seal Ultimate will assist in my head gasket issue with this vehicle?
Anita Minor
Nov 11,2019Giving it 4 stars since im only on the third day with no leaks, but long story short my 2011 chevy cruze LS was leaking antifreeze and the heat wouldnt work, took it to the dealership to have it looked at and my water pump needed to be replaced...googled this product and had good reviews and some bad, figured i might as well give it a try and so far so good!
alan g
Nov 09,2019This product is brilliant , it really does do as it says on the bottle
Gurtake Singh
Nov 08,2019I bought k seal after reading all the reviews as I had a coolant leak and I bought the ultimate from euro car parts as I was told if helps I’ve tried it and i still have the problem on my Vauxhall zafira do I try another bottle or is there something else I can try
Deborah Axford
Nov 07,2019I had a slight leak from coolant tank and was sold K-Seal (pour and go) from motor factors as a cheap solution . My car is a 2013 Citroen C4 VTR+ The product sorted the leak but glued up the heater matrix hence no more heating / warmth through the vents also for demisting windows. Usual garages couldnt fix it so had to go to Citroen dealer and cost £504 for replacement heater matrix and am now pursuing legal action against K-Seal or wont accept the product causes such problems despite plenty of other cases on the internet... I suggest K_Seal is only good on old fashioned systems
Pamela Bulger Mostoller
Nov 07,2019I have a coolant leak not exactly sure where it's coming from but used a bottle of this and for a few weeks it worked great but now I have a leak again. How many times can you use this product on the same car please? I do have a 6 cylinder and just read where maybe I should of used 2 bottles so now if I go get another bottle should I use 2 or just 1 again? I am so confused as to what to do..someone please steer me in the right direction..thank you
Giles and Kate
Oct 25,2019Fixed a massive leak in the head of our pickup truck. 9 months later still going fine :) Thanks! Update: 3 years later, 40,000 miles more, still fine!
Patrick mccann
Oct 22,2019Don't waste your money on this rubbish, its a scam. I have a minor heater matrix leak and paid £13.00 for a tiny bottle of this rubbish, followed the instructions and my matrix leak actually seems to have got worse. Again folks forget this stuff, its just another scam!!!!
Ram Kilic
Oct 20,2019Following my review back in August I used the replacement bottle on my Citroen Xsara and haven't noticed any symptoms since then. Colin from K-Seal was quick to respond and advice.
James O'Quinn
Dec 14,2019I don't know if it clogged the leak, but it sure clogged my heater core...