Just in reply to this: https://www.talkmorgan.com/ubbthreads.php/topics/832743/re-coolant-dipstick#Post832743

In May 2023, they issued redesigned coolant tank caps (mine is a MY22 Plus Four). I was about to head off for a long trip and couldn’t drop the car off, so instead I was mailed a new coolant cap - along with instructions for how to refill the coolant:

“ Do this when the car & engine are cold - You need to open passenger side bonnet,
Take old cap off coolant tank, suck out all fluid in the coolant tank with syringe - bottle it all up, then put back exactly half a litre, and fit new cap. The warning sticker should also be fitted to the side of the coolant tank.

Less fluid gives less pressure. Should equate to it pressuring the whole system less. “

I didn’t dilute the coolant - used BMW HT-12 (Green). The 50% level warning sticker (as others have said) is the fill level, not the dilution.

Last edited by Gonze; 26/10/25 07:53 AM.