The saga continues.....
The radiator was in fact badly clogged and I had a new core fitted. There were still bubbles in the water and so I decided to go ahead to the next step and remove the head. The car stood for a month or so after which the level in the header tank dropped and the level in the sump rose.
I removed the plugs and turned the engine over on the starter in order to avoid risk of hydraulic lock. No water came out of the cylinders but placing a screwdriver through the plug hole in No 4 (the one nearest the exhaust outlet port) revealed the presence of water. The engine still started readily (after replacing the plugs!) but after a short running of the engine the oil was cloudy...
The head has now been removed - I confess by someone else as I am rather frightened of overhead camshafts, my background being almost entirely side-valve - and the report is that there is a crack on the outside of the head. Plainly that isn't the cause of water in the bore but needs attending to. I am going to look at the engine on Monday morning first thing.
In the meantime has anyone got any recommendations as to repairers - the ones nearest to me are Slinden and Surelock (both well known in the VSCC world). I have found a company in Burton - Lockwell Engineering - who appear to use a similar process to Surelock but I know nothing of them. If I stick with the head on the car it will need repairing - and it has the advantage of having been twin-ported. I do have a spare engine whose head has not got that advantage - and whose condition is unknown.
All opinions gratefully received - my e-mail address is
michael.elsom@btopenworld.com if you don't want your views made public!