Bar's leak

[David Stepney]

I, too have used K Seal, as Barr’s seems to be unobtainable round here. I had a persistent slow drip from the base of the drain tap on my radiator when I first had the car. A dose of K Seal cured the problem. However, given that the leak was at the very bottom of the system, it is small wonder that the sealant would sink to that position. Having said that, notwithstanding the lazy water circulation of a thermosyphon system, I would imagine  some sealant would be carried round to seal other leaks.

For the cost, I would put some Barr’s or K Seal in and see how it goes.