Allis 190 diesel fuel pump

Hi again everyone
I have a 190 xt diesel with a Roosa Master fuel pump. For the most part it had been running great, except very intermittently it would suddenly rev up or down every 20 minutes or so. Like a sticky throttle plate, it had this problem since last year. I was out plowing yesterday and was just about getting done when it started reving up and down more and more out of my control. What was once about every 20 minutes was now 30 seconds. It also started to hesitate. I figured I better check it out so I idled it down and it started knocking a little. I went to shut off the tractor and it wouldnt shut off. I had to plug my hand over the intake. The linkage seemed good as it moved the arm for the fuel shutoff and I took the top of the fuel pump off and everything seems to be intact. I was thinking something could be wrong with the metering valve but I am not too familiar with the setup. Any thoughts or direction would be greatly appreciated as to what the problem could be. It is due for a fuel filter replacement and I will replace it also.

I'm sure Ed is right, but don't think a rebuild will solve all your problem. It is sucking air from some where. Most likely place on XT is the two bottom outlets on bottom of tank. Unscrew the two settlement bowls out of tank, letting some fuel to run out. Look in top of assembly for foreign matter and clean out. After putting back together, should have a good stream out of line if unhooked at primer. If not, unhook at settlement bowls and blow back through. DON't BLOW BACK INTO TANK. Change filter and check for loose fitting.      MACK

I had the same issue with my 190XTD when it raced and wouldn't shutoff. I went to the back of the tractor and turned off the valves underneath the tank at the sediment bowls on each side and it ran out of fuel. By the way, about 10 operating hours after this happened the engine died and it wouldn't restart while on the road. I was about a 1/4 mile from my drive way so I had to tow very slowly since it died on the road. After letting it sit for a day and priming the pump, I got it started long enough to get it into the barn. Aside from this racing issue, mine would die off and on to the point, I couldn't use it. Unless you know that Pump has been rebuilt lately, it is most likely the cause. You should consider deinstalling and recommend sending it to Ed for repair before you get stranded. While you have the pump off, you should start at your sediment bowls and clean fuel lines, return lines to clean up everything. I had some really bad gunk in my tank and one sediment bowl's intake hole was completely blocked with a wooden splinter. I cleaned out all of my lines prior to removing pump just to make sure it wasn't the pump. The inability to turn it off points at a bad pump from my experience. I have a detailed post on here about how I removed mine and the troubles I ran into so recommend you read up before removal. Be sure and borrow Eds tool for re-installing the pump to avoid rolling the shaft seal like I did twice. :-)

Good luck.