Lately my 2000 F350 has been blowing blue smoke out the exhaust when I first start it in the morning. I have also been loosing coolant. Today it quit running after about a minute and would not start. I pulled the fuel filter and sucked all the fuel out. There was orange coolant in the bottom of fuel cavity. I had the cups and injectors replaced for fuel in coolant Dec.2018 and have also seen a little fuel in coolant lately. How can fuel be getting into fuel filter cavity?