K-Seal Coolant Leak, 236ml | Multi-use Car Radiator & Head Gasket Repair Sealant

It might work in a very hot engine with a cracked Block but it most definitely does not work if you have a water leak from a water pump or any type of flexible hosing I tried to use it as an emergency to stop my water pump leaking on the Jaguar XF but it did not work total was

A mechanic recommended it after I sought help with a coolant leak. Couldn’t figure out where exactly the leak was. Was unable to locate any visible leak. The Color of exhaust smoke gave no indication(no white smoke). Engine oil looked ok. Tried it as a last resort than having to spend a lot more on replacing engine head gasket. Worked for my car. No more coolant leak. 🤞🤞🤞

Seemed to be working, naturally the full extent can’t be measured, but didn’t regret the purchase, good value for money, worth a try to be honest, easy to use.

Great product. I had a difficult to locate leak on my cooling system, the tank was empty/below the minimum line every morning. I topped up with new coolant to minimum, added all the KSEAL, then finished topping up with coolant to just above the max line & took the car for a good half an hour drive with the heating cranked up to max for the duration of the drive. Check my levels this morning & I haven't lost any coolant overnight. Perfect product for fixing the job.

Yes it works

Does not fix oil to water leaks

Does what it says on the tin stopped the leak easy to use 🫡

I used K-Seal for a radiator leak before I could get the car into a garage for a proper repair, and it worked well in the short term. It stopped the leak and gave me enough time to arrange a permanent fix without constantly worrying about losing coolant. That said, it is important to understand what this product is. It is not an end-all solution and it should not be treated as a replacement for repairing the actual problem. It is more of a temporary measure or a way to buy some time before getting the issue properly diagnosed and fixed. For what it is designed for, it does the job well. Just don’t expect it to magically repair a major cooling system fault permanently. A useful product to keep as a temporary emergency fix, but always follow up with a proper repair.

Seems to stop leaking from plastic header of the radiator.

Salut à tous j'ai acheté le 16 Mars 2026 il a duré 4 mois sur ma clio 2 phase 2 de 2003 pour moi excellent produit et simple a utiliser juste a mettre dans le bol de liquide refroidissement voilà

merhaba aracımda 2-3 günde 50-60 km kullanım sonrasında 500 ml kadar ciddi bir su eksiltme problemi vardı 20 şubat günü ürünü kullanım talimatına uygun olarak yedek depo içinde full antifiriz varken kullandım ilk kullanım sonrası 250 ml kadar bir eksiltme yaptı üzerini max çizgisine kadar tekrar antifiriz ile tamamladım 45 gün kadar oldu her hangi bir eksiltme olmadı şu an için daha önce kulladığım bir çok üründen daha başarılı

Fungerade mycket bra. Jag är nöjd. Bara att skaka burke jättenoga först. Sen hel i allt

It really works! Saved me alot of money