Where exactly is the inlet manifold drain plug on a BX16/19 and is it *imperative* to remove it when draining the cooling system? Haynes BOL tells me to remove it at the same time as I loosen all the bleed screws... but there's no picture of the actual location, just a simple schematic diagram of the cooling system where it's arrowed next to the water pump... I've looked and I can't find anything obvious.
Cheers,
Mark.