The best for you to do is figure out how to make it happen if you can. When it does, crack open a fuel line to see if you are moving fuel. You don’t have to take the line off, just a turn or two will do. I don’t know the engine, but there has to be a transfer pump on it. Crack the line on the out going side. If you have fuel there go to the injection pump and do the same. Till you find out where the fuel stops. You may find out you have fuel all of the way to the injectors. Then it could be a lot of things. You may have fuel, but not enough pressure. You can just have a sensor going out on you when it gets hot. Seen that before plenty of times. Seems you only have the problem when the engine runs awhile. The best thing to do is find a scanner so you could see what is going on when it happens. I don’t have one for a Cummins or I would bring it down and go fishing with you till it shuts down. Ask the Cummins guy if he wants to go fishing on a Saturday and bring his scanner. I don’t even know of anyone that has one I could borrow. You have my number, call me when you are messing with it and I will try to help you out.