Quote:
I know of a Stag which overheated with Evans with little warning and by the time the owner was aware there was a problem the engine was so hot than he burnt his hand on the cam cover.
The thing is that that very scenario can and does occur with any coolant type in a Triumph V8 or slant four.
There is a warning about it in both the 1850 and the Sprint BL workshop manuals,
when the coolant level drops the temperature sensor will still read "normal" because it is being cooled by air flow.
This is a drawback of sighting the sensor so high up at the front of the engine.
(I have not seen a BL workshop manual for a Stag but presumably the same warning is printed there?)
Rather crudely you can keep the heater set to hot and periodically check it hasn't turned cold,
or you can avoid this occurrence by using a suitably positioned header tank that has a low level warning.
Ian.