Quote: If you want to clean out the rust and sludge use vinegar, fill it up. let it sit for 1-2 days, rinse it out and refill with coolant. there won't be anything but good clean stuff inside when you are finished.
Like drain the system as much as I can....and fill it up completely with vinegar?
Be sure and use white vinegar for this. Don't use apple cider vinegar unless you're gonna make salad dressing.
