At least on the V6 this ‘tap’ is very hard to get to. I say ‘tap’ because thats what it appears to be on my RSV. Only needs to be turned 180 degrees counterclockwise to open it.
I ended up using a 19 mm 6 sided socket on a 3/8 drive ratchet to turn it very gently until it would start draining, and then very gently back again. No way I could turn it by hand - combination of difficult access and tap is quite stiff. Obviously if doing this use a socket that is a fairly tight fit
Also noted that only about 5 (of 9) litres drains out each time so did this:
- Refilled with distilled water, ran engine for about a minute and gave it a few revs, and redrained, twice,
- Then poured in just over 4.5 litres of concentrate (Nulon Gold allegedly compatible with everything)
- Then topped off with a few hundred mls more distilled water.
All up cost of about $50 for coolant snd $25 for the water which if done every 4 years would be $19 per year.
Main thing to watch out for would be damaging the tap at bottom left of radiator.