I just went through a 2007 WR450F I purchased recently: suspension bearings, valve lash check, carb rejet, etc. Now back together, it is flowing water from the expansion tank overflow line.
I have the radiator overflow line routed into the bottom nipple of the expansion tank. The top nipple of the tank is the overflow hose, which is puking water.
I filled up the radiator past the fins to about the neck and I poured some water into the tank so it was about 1/3 full. Should I have left the tank empty?
During the restoration I pulled the water pump cover, replaced the o-ring, and checked the impeller for play.
The overflow water is warm/hot to the touch but not scalding. It is not boiling out of the radiator. I've tried two different radiator caps, a Mylers high pressure and the stock cap.
Edited by 2strokeYardSale, April 22, 2016 - 07:59 AM.