cooling system gunk

[thejimrose]

pantelis - good info, i have often wondered what the best way to really
flush out old coolant to allow for new [different] coolant to be used.

i haven't heard in my audi travels of a 'cleaner / neutralizer' for cooling
systems. any idea where to get such a thing?

i r+r'd the coolant on the a4 several months ago. the head was done on my
car at some point, the coolant i took out looked like used motor oil.
literally.

i ran some prestone flush through it, then several cycles of distilled
[fill, run, flush, repeat] until it came clean. i then replaced with the
correct red audi [pentosin] coolant.

my coolant still shows fine in the overflow tank, but i might drain a bit to
see what's going on in the radiator.

it's a messy PITA job. but any lurking slime / sludge / goo / funk /
schmegma from the old/bad coolant is like a thorn in my brain.

cheers
jim