After my 4850 nightmare I had a 4450 blowing water out the radiator. Took the head off and sent it to a machine shop and they surfaced it and checked it all out said they thought the head gasket was the problem. Put it all back together new head bolts and gasket. Radiator will still burp water out once in a while. Filled the radiator up and cranked the engine over with out starting and looks like it burps air out when one cylinder is on compression. Thinking one of the sleeves is cracked. Guess I will pull one injector at a time to find the one leaking then pull the head again and the oil pan to pull the bad sleeve. With my luck it will be 5 or 6 and have to pull the oil pump also. Then another new head gasket and new head bolts. Guess I am smart enough to be dangerous but not smart enough to fix it right the first time