The ongoing saga of my GT6 radiator:
Bought a used, but tested good, replacement radiator and had it fitted yesterday. As soon as system was hot and pressurised, coolant appeared at exactly the same spot near the filler neck as on the original radiator. Many rude words later and much checking and rechecking of hoses for pinholes, clips for tightness I decided in desperation to try a new radiator cap, courtesy of my local MG specialist.
Mirabile dictu - I no longer appear to have a leaky radiator.
Has anyone got a logical explanation as to how the old filler cap was able to create a convincing impression of a leak ?
I now wonder if the repair to the filler neck on my original radiator had actually been effective but disguised by the radiator cap creating a problem.