K seal/rad weld in its self can cause lots of problems.
To Malcolm's suprise, when he tried to drain the coolant from my TZD, nothing came out of the bottom of the rad when he pulled off the bottom hose!
So much rad weld had been used that it had blocked up the rad and also set solid in the pipe that runs from the bottom of the header tank to the rad. I managed to source a 2nd hand TD rad from Billo and this has worked fine. Havnt yet managed to clear the old rad yet, tried putting water in the top but nowt comes out at the bottom so i suspect its truely knackered.
All the overheating/water loss with the original engine was caused by the loss of a bolt holding a plate on the side of the engine, should have been 2 but one was missing. A simple fix really.
So far so good, been to Looe twice recently, no loss of coolant nor used any oil so Malcolm has done a grand job on her.
Andy