Williams/1.8 16v strange water loss

[Bmg]

Please could someone point me in the right direction I'm losing water every day with no signs of a leak no morning missfire no condensation out of the exhaust no oil in the water or vise versa just disappearing I've done all the necessary checks found nothing I've noticed that the electrical water pump doesn't come on but I don't know if it should like I say it's a 1800 16v with a Williams engine and pretty much everything else any advice would be much appreciated

[16v_paddy]

Have you tried putting some UV dye into the coolant to check for leaks?

[northy]

Any updated to this BMG?

Try pressurising the cooling system up.

[Sam16v]

I’d check the silly things first, Expansion bottle cap? Cracked bottle? Leaking hoses, rad etc. Heater matrix?

[white16valver]

Heater matrix is a good call - doesn't it make the passenger side footwell damp?

Is the radiator all one metal or a mix of metals (and/or plastic)? Could be weeping at the joints - replacing the rad in another car recently fixed my mysterious water loss!