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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
Kamalendra Vattikuti
Oct 05,2021I had engine misfire issue on my Volvo xc60 r design 2015. Mechanic changed coils and sparkplugs for $1300, dealer changed injectors and charged 1800 but still same issue. Used kseal and followed instructions. got fixed in few minutes. No problem drove up to 1000km. But not sure how long it will stay? But for now problem is fixed. Saved me 5500 for head gasket repair.
Dale
Sep 20,2021This stuff is awesome I had an old 1997 fiat punto that had a leak in the radiator so before ordering a new rad I tried this in it and stopped the leak within 25 mins was gobsmacked the heating inside the car was back where as obviously due to the leak before I was blowing cold inside the vehicle , my only regret was I had already ordered the new radiator before purchasing this stuff, I now think I have a suspected head gasket failure on my suzuki swift sport and I'm considering buying this to see if it can cure the issue car runs great but found a bit of oil in the water hose just not sure which product k seal would you recommend to use :)
Art
Sep 19,2021I've had an ongoing coolant leak for 3 years or so from my land rover defender 200tdi. It has been losing about a litre every hundred miles or so. My local LR specialist had it down as a leaky hose and I have tried various things to try to find the leak without success. The garage eventually diagnosed a cracked block - recon engine required. I really needed the vehicle for 2-3 months so tried K seal. The engine has worked very hard setting up events on and off road, high and low range gears, and is now only losing about 1/8 litre every 100 miles. I put the k seal in about 4 weeks ago. I am wondering if the leakage will continue to decrease, or if it is worth using a second bottle. I am really pleased with the results - it is certainly getting me through the events and I will monitor the progress over winter when my mileage goes down. Update- the leak increased and I was losing about 1/4 to 1/2 litre every 100 miles. I emailed Colin and on his advice I used a second bottle which he kindly supplied. After a further 2 weeks I am now losing no sealant whatsoever. I am overjoyed with the result.
Dean
Sep 04,2021Back in 2018, my Omega which at the time was on 212,000 miles developed a coolant leak. The garage I use did a sniff test and said that it was the head gasket. Because I'd had the head skimmed twice before during my ownership (I bought the car on 40,000), they couldn't do it again. As I had no money for a replacement car, they said to just drive it locally and keep an eye on the water level all the time. On one of the previous occasions when the head gasket failed, the AA man put in some K-Seal to last me until I could get the work done, so I looked into that again. On that occasion I opted for the K-Seal Ultimate and whilst I always kept a close check on the water levels, it lasted superbly until a few weeks back when I noticed coolant loss again. It was then on 241,000 miles, so the K-Seal had given me almost 30,000 miles of driving. As I am now in an even worse financial position than in 2018 and with an important 500+ mile return trip to Wales looming, I felt that the only chance of getting us there was to give another bottle a try. I am so happy to say that, 1,000 miles later, the coolant level appears to be holding up again. I am very grateful to the manufacturer for keeping my 19 year old car on the road and for keeping us mobile.
gary Walton
Sep 01,2021Well K Seal, if only I'd read the comments before buying this poison. I Had a small leak, thought I know I'll try K Seal, I did everything right according to the bottle. To cut a long story short, this stuff wrecked my engine, causing it to wreck my water pump, welded up my radiator and bottom hoses and clogged up my expansion tank. Total cost over £800 of damage.
Kr Patel
Sep 01,2021K-Seal Ultimate: It worked on my Chevy Impala to seal intake gasket leak -I have tried many others without success. Finally I decided to try KSeal Ulimate and I solved my problems.
Sandra
Aug 28,2021I used k seal on my Ford F-150 for a radiator leak at the bottom. It stopped the leak then I loosened the pressure cap on radiator and it started leaking again? Should I try another thing of k seal and not loosen the radiator cap this time?
Gary Audley
Aug 20,2021Words fail me, I have a 2009 mercedes sprinter van that had catastrophic water pump failure, I mean it was leaking like a tap, I tried K Seal ultimate, and wow stopped it immediately, saving me over £311 which the garage wanted to fit a new water pump and belt. I'm gobsmacked. Truly the best investment you'll ever make, yes it's £42 a bottle but massive savings. Well done K seal awesome product
Ryan James
Aug 20,2021Man. I've had a persistent leak from the gasket on the water pump on my 2001 Honda Odyssey. Five mins with this running in the engine, zero leaks. Bone dry. Even 20k miles later. EXCELLENT product
Bill Nsr
Aug 20,2021I used this product for my renault twingo which was leaking from the radiator.. it worked instantly and it felt like magic. However today after 3 days of using your product the leak started all over again. I thought your product fix is permanent. Any advice?
Dan Becker
Aug 19,2021Basically I’m an 70-80s old school mechanic and I’ve found that mechanics in a bottle usually don’t work ((BUT)) KSeal sealed an unrepairable head leak without some serious $$$$$$$$$ for a disassemble and rebuild which the young lady did not have my buddy tossed me a little bottle of KSeal and in 15 minutes of running it sealed . A while back I seen her in that old B.M.W I asked her how the leak was she replied it never leaked again . Bravo to you KSeal IT REALLY WORKS !
Helen
Aug 09,2021I had a coolant leak which lead to a pool of coolant in my pasanger footwell tuck it to my local garage which wanted £900 £450 for a new heating matrix and £450 to take the dashboard out to my horror. Saw this product on yourtube, used as directed and poof £900 bill gone absolutely brill.
Graham marshall
Jul 30,2021Core plug had a small leak , saw the product and thought wow , will try it . Added as directed , allowed a few days for product to work , still leaking so had to get garage to replace core plug . Emailed Colin few days ago before posting this review , alas no reply so here’s my review ..!! Waste of money and £13.99.!!
Christopher Orpin
Jul 30,2021No not worked at all. Day one after short run fine today water loss again
Ruben Hernandez
Jul 23,2021I had a pretty big problem with my car. Water to oil leakage, probably a cracked cylinderhead or engine. I didn't have the time to replace the engine or cylinderhead. So I tried K-Seal. I thought; what the hell, let's try it maybe it works. I was using 1liter water on 15km's, thats a lot. Drained the oil, put new oil and coolant in added K-seal to the coolant. I let it run for 1 hour on 2000rpm. Checked the fluids. All still oke. Now 10000km later still oke. Thanks K-seal.
Paul Wilson
Jul 21,2021THROUGHLY flushed cooling system before adding K-Seal and I got even better results than the fist application15,000 miles ago. Engine was running supper smooth 186,000 miles covered, but using 6ml of water per mile. Flushed system 3 times and water use went up to 8ml per mile. added K-Seal and did 80miles in one run. water consumption down to 1.5 ml per mile.
Eddie Reed
Jul 15,2021I had a coolant line on my turbocharger leaking shop wanted 1200 dollars to put a 5 dollar line on my truck I read about k seal 2 days leak completely stop iam amazed with this product I would recommend it to anyone wanting to save on these ridiculous shop bill give k seal a try first what have you got to lose
Mark
Jul 07,2021This review is to comment about the money back warranty. It is for real. I tried K-seal ultimate on a Ford tractor and the head gasket was just to bad to seal. I submitted my warranty claim and the refund was in our mailbox in 4 days. I was astonished with the expedited response. Thank you.
Carlos Robles
Jul 05,2021Didn't think it would work. Sealed my water pump leak. Saved me 350.00. Thank you
Mabb
Oct 10,2021Had a very small leak on Renault captur losing only small amount of coolant ,took to garage they tested for blown head gasket came back negative and said keep a eye on it ,well I found where the leak was coming from and could feel the coolant drip on my finger put a bottle of k-seal in left engine running for 30 minutes and guess what no more leak for £12:99 I could not be more happier after reading all the good reviews I’m so pleased I tried it deffo worth the price and I never normally leave a review