Atfer this about a couple of weeks later the water in expanision bottle tuned to oil.It seemed to get thicker and thicker had oil cooler changed and system flushed out a coulpe of times still traces of oil. Water bottle now keeps emptying its self of water after travelling 20 to 40 miles when stopped and engine is warm. A couple of seconds before this happens the water is bubbling hot so still no futher forward with the problem.