98 S70 petcock drain -- how much?

[mar601]

When you open the petcock on the radiator, generally how much fluid comes out of the entire system? Half? more? less?
-- many thanks

[scot850]

Maybe 2/3rds? The block and heater core will hole a certain amount. There is a drain on the rear of the engine block. If it has not been undone in a long time they can get sticky. You have the opportunity to remove the drain completely, free it off and use some anti-seize on the threads while you have the system drained.

Neil.

[mar601]

Good -- thanks. I mistakenly put some Dexcool in there (as it turns out, only about a quart) but still want to do a couple of drains and get the right stuff in. Approx 2/3's is good news.

[abscate]

I usually drain at the lower radiator hose and flush by feeding water into the bottle with the lower hose off for 15cminutes, engine idling. Stay with it and watch it like a hawk so you don’t let the hose slip off and cook your motor. Don’t go off on another errand!