you dont need to know how much your washer bottle holds to get the mixture correct
all you need is a container you know the volume of i.e. a 1.5ltr pop bottle
if you need a ratio of 2 parts water :1 part wash thats 3 parts in total divide the 1.5 ltr by 3(total parts needed)
so 1 part is 500 ml and 2 parts is 1 ltr
so fill pop bottle with 1ltr of water and top up with 500ml of screen wash
(always add the screen wash last this way the wash wont bubble up)
then fill up washer reservoir easy
