So one of my new guys grabbed the wrong fuel and put 10 gallons of gas in my skid steer and it started running like crap, (go figure), they couldn't figure out what was wrong with it so they changed the oil and fuel filters they would run it until it just didn't want to go and try something else for a day. I don't think they got to much time on it but I do think they got some time on it. I discovered the issue as soon i had them get me a sample of fuel and smelled the unleaded in it. so siphoned out the tank, there is no drain on it. changed fuel filters filled it with 10 gallons diesel added 1/2 quart of trans fluid to it. and it starts and runs kinda sputters at idle and some blue smoke, if you accelerate it spits and sputters and does want to run it will not move the machine if you let it idle then it will start to move the machine at idle but not under power, I had a guy that was helping me diagnose it and this is what we came up with. with it running we can crack each injector open and can tell the engine drops off for every cylinder which i was told that the injectors are working then, he said that if the injection pump was bad that it wouldn't run at all. And that it was probably the fuel pump, there is a electric fuel pump on top of the fuel filter housing but I am assuming this is the priming pump and I don't see any other fuel pumps like a lift pump, but I am really not sure. if anyone can help I would greatly appreciate it. when it runs it has blue smoke from the tail pipe and when it spits and sputters is when it puts out the most smoke.