For the avoidance of any doubt.

Here's my new screen wash tank, it's only job is to hold cold Prestone screen wash fluid, and feed it to my new remote screen wash pump. The tank sees no heat or pressure, and nor should it!

[Linked Image]

And this is my new header/expansion tank, which is specifically designed to hold hot coolant that on Monty is carefully managed in a 79c - 95c window. Operating pressure is 7psi - 10psi, with the relief cap venting/releasing a pressure spike between 14psi - 16psi.

[Linked Image]

I trust that's clear thumbs