Thanks for your reply Steve, Yes water level goes well below the top of the radiator core. The previous owner ran the car out of water with a different engine so I suspect the radiator. I was playing with it today and the water level slowly rises and runs out but when one revs the engine the level d...

I confess firstly that my car is a 1948 MGY with an XPAW engine (modified to fit) but this question should be a general XPAG (prior to MGTF). My car uses water prodigiously (two litres in 10km) It appears to be pumped out of the overflow pipe. No exhaust gases are present in the water and the engine...