Not IH- Gehl 4640 Engine Issues

We are having issues with our Deutz Diesel Engine on our Gehl 4640 Skidsteer. Not IH but thought maybe someone on this site could help. The engine will run for a minute or less, then it quits, like it is running out of fuel. The settup on it is as follows: Fuel tank, inline filter, lift pump (run off of engine, not electric), spin on filter, then what seems like a piston or diaphram pump for each individual cylinder, then line to injector. We replaced the filters and made sure the tank was full, and drained the bottom of the fuel tank to remove any dirty fuel or water, none of which we saw. We have fuel being pumped through filter when motor is turning over, and we have fuel being pumped from overflow line from injectors. So it seems like we are getting plenty of fuel to the injectors, but it will still only run for up to a minute, then it will not start or even try to fire unless it sits over nite. We cracked lines to make sure it is not air locked, run it with the tank fuel tank cap off to make sure a vaccum wasn"t preventing proper suction from tank, and even forced fuel into the spin on filter by pumping fuel from our bulk tank directly into the filter, bypassing the lift pump. It still only runs for a bit, then quits,and must sit before it will even try to fire. Anybody familiar with these motors have any suggestions? Thanks

check for a plugged return line, had a 656 with a plugged return line ran a few min then quit

You said that it runs for a minute and stops. After it stops when you turn the key to start it will it smoke? To me it sounds like you have a bad fuel pump. If you have like over a 1000hrs on it and it has never been changed I would try the fuel pump. They do go bad. Before all this happened did the skid loader feel like it was losing power? Will it start if you give it a shot of either after it quick’s. Nothing electronic controls the fuel on them.

You said that it runs for a minute and stops. After it stops when you turn the key to start it will it smoke? To me it sounds like you have a bad fuel pump. If you have like over a 1000hrs on it and it has never been changed I would try the fuel pump. They do go bad. Before all this happened did the skid loader feel like it was losing power? Will it start if you give it a shot of either after it quick’s. Nothing electronic controls the fuel on them.

Is the pump before the spin on filter a low pressure lift pump or is it actually the high pressure injection pump??? I assumed that since there wasn"t much of a filter before it that it was just a lift pump, and that each injector had its own small high pressure pump (I"m obviously no diesel mechanic). It doesn"t seem like it smokes much when attempting to restart. Did not notice any horsepower decrease, but not saying there wasn"t any, and it will run on a bit of ether, but doesn"t continue to run off of diesel. It has over 2500 hours on it and the pump hasnt been touched. It seems like it is supplying enough fuel pressure thru the filter if it is just a lift pump, but doesn"t seem near enough pressure if it is indeed the high pressure injection pump, though I still think it would have been filtered better before it went to it. Thanks again- Jeff

Also, if the pump is out, or weak, would it be able to run a while, or would it just not start? Thanks again- Jeff

What kind of fuel shut down does it have a manual cable or does it shur down with the key switch? If it is a key switch shut down there is where i would be looking as you either have a problem with juice getting to the shut down solenoid or there is a problem inside of it . So i would check and make sure that you have juice at it when it does shut down and if does not then ya need to back track to the key switch to find where you are loosen contact , If you still have juice at the shut down solenoid then the problem is in the solenoid it's self .

Vet-It has electric shut off- I thought that might be the problem, but it still has fuel at flowing out of the return line after the "mini pumps" when turning the motor over after it quits, and it didn't make sense that it would run for a while and then quit, unless the solinoid was over heating or shorting out. But I am going to look at the shutoff again. Thanks!