So I finally got a new radiator for my truck. I flushed the engine and the heater core with the garden hose forward and backward until I got clear water to come out. I installed my new radiator and filled her up with fresh coolant. Then I ran her for a while to burp the system and drove her around the block. When I checked the coolant it is turning brown. Is there a way to clean out the system better than I already have and stop the coolant from turning brown on me?
http://www.jalopyjournal.com/forum/showthread.php?t=386736 some good info/hot debate here. couple coolant changes might just do it, or a can of one of the milder engine flushes, like prestone. just make sure you blast it out again in the same manner you originally did, and flush the radiator with water afterwards. don't want to leave those chemicals behind.