Block Sealer and Antifreeze

Nov 09, 2003 3 Replies

Does anyone know where I can get a Block Sealer in the UK that works with Antifreeze ? I'm using Halfords sealer at the moment which works a treat when its in but once I flush it out and put antifreeze in the engine fails again within a 100 miles or so. Regards, Steve


Why do you flush it out? I never flush out my radiators and if I use Radweld (OK, OK, those who wince at this) that works perfectly well.

Rob Graham

I use Radweld

Block Sealer is not the same as Radweld etc. Radweld will not block a crack in the cylinder head or leaking head gasket where as block sealer does. It is very heavy duty and not designed to be left in for more than a few days. For some reason it is incompatible with anti-freeze. I've ordered a product called K-Seal from a company called Kalimex which they claim is compatible with Anti-freeze but I wait and see if its up to the job.

Regards, Steve

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