I have a Case 580ck with a 188 diesel engine that has started to stale and sputter when I put it under a load. It was running great and just started this all at once. It seems to run fine unless I try to push into something with the front bucket or pull up a hill. It starts and idles fine. It will accelerate smoothly and sounds good at high RPMs. When it starts to sputter I can press in the clutch and rev it up and it will continue to sputter until it gets the RPMs up and then it seems to catch up and sound normal again. When I release the clutch and put it back under a load it will pull strong for a few seconds and then start to miss again. If I release the accelerator and let it idle for a few seconds, then reaccelerate, it will pull strong again for a few more seconds. It does not seem to start smoking any worse than normal.
I had refilled the fuel tank about 2 hour earlier, and assumed that I may have picked up some bad fuel. So I drained the tank and refilled it with new fuel. I have changed both fuel filters, disconnected the air intake from the filter assemble (temporally of coarse) and cleaned the injector pump screen. I checked for adequate fuel flow to the injector pump, and blew compressed air back though the fuel lines to the tank (just for good measure). I disconnected the fuel return line from the tank, pump and injectors. I disconnected the fuel shut off linkage and tied it back to make sure it was all the way open. I ran 2 bottles of injector cleaner though it. None of these things have seemed to help it at all.
I removed the high pressure lines from each injector one at a time and did notice a miss and a changed in RPMs each time I loosed one. I am a bit new to diesels but I was not impressed by the flow of fuel that sprayed out the high pressure lines to any of the injectors. I would say that the fuel would not have spayed a foot or more. Does anyone have any other suggestions on what the problem may be? I am running out of inexpensive things to try. I am hoping it is something besides a bad injector pump.

Thanks,
Gabe

Make sure you don't have something obstructing the air cleaner. This could cause problems at higher RPM when more air is needed. I had this problem in the winter when water in the air cleaner froze and limited the amount of air getting to the intake manifold. I know you don't have icing, but maybe something else is fouling the air cleaner.

I disconnected the air intake hose from the filter assemble and it made no diference.

Thanks,
Gabe

Gasoline in a diesel even in small amounts will cause nearly a complete loss of power. Too much and it will NOT run! Better check the fuel to see if it's alright. The next time it stalls under load, quickly check the amount of fuel getting to the pump. Maybe something is in the tank that blocks the tank outlet? If everything checks out alright, you've answered your own question. It's the pump! Good luck.

I am almost positive that there was no gas in the tank. I have since burned all 5 gallons of the new diesel out (with the injector cleaner in it). I refilled it with 5 gallons of new, clean fuel today and it still runs the same. Can anyone recommend someone to rebuild this pump for a resonable price. It is a Roosa Master DBGFCC431-27AJ 459368 A-35774

I have had the same problem with mine on and off.It allways seems to be the fuel valve ontop of the injector pump.This valve is a restrictor with a spring and ball inside.If it sticks open alittle you get a miss at power.If it sticks wide open the engine will slow and stop.DON"T take that pump off before checking this first.

I can not seem to find the spring and ball that you are refering to. Where exactly is it located on the pump?

Its the first thing out the top of the pump in the return line.Often has a brass elbow just above.

Don't know where you are located, but Stateline Diesel Service in southwestern Michigan is outstanding. If you want the pump turned up slightly, they can do that too. Their number is (269) 663-8571.