Long Diesel Tractor Won't Re-start

My dad's old tractor had been parked in a shed and not started in several years. I got it to start, but the engine stopped running after running for about 5 minutes and won't restart. If you loosen the fuel line at an injector while cranking the engine, should the fuel spray out? I read some advice on another tractor which said to take the return fuel line loose at the injector pump and try starting it. What does this do, bleed air out?

yes, fuel should squirt out at the loose injector line, open the throttle--after sitting, my guess is to back up from injector pump, check fuel flow from tank, filters, water in fuel. i think you have a cav style pump, it usually doesn't have internal problems that stops up return system

the only thing loosening the return line does is if return line is plugged tractor wont run , loosening line allows to start tractor in trouble shooting.
to get air out you must crack injector lines till you have fuel dribbling out then close them and start tractor.and no it wont spray out. has no way to pressure up.

You can loosen the filter connections, pump connections and injectors and then just keep cranking till there is fuel coming out of all of them. You might have to charge your battery a couple of times or just leave it charging in the tractor. You can also use a large syringe with a rubber hose that fits over your fuel lines and infuse diesel thru every line you can get to. It is also useful to cut an old inner tube with enough material to allow it to be zip tied and duct taped to the fuel filler tube with the valve over the filler tube. I would first blow air back into the fuel tank from the fuel pump, this eliminates any obstruction at the beginning point, reconnect, and Then you can hand pump it or just give it short burst with an air compressor which will get things going in the right direction. Find the line from the fuel tank to the fuel pump and get fuel going thru that one, and then thru the filters, pump, and finally the injectors. I would change the fuel filters now and prime them with a syringe if necessary since you already have air in the lines you only want to bleed it once. More than likely you will find water and crud in the filters.

Make sure fuel is coming out of the tank and thru the filters,if you have fuel to the pump the easiest way to get it going is to tow it with another tractor might take pulling it a quarter mile to get it to purge the fuel lines and get it to start.And make sure the fuel isn't cut off at the tank. What Model Long is it BTW?

Good suggestions by Traditional Farmer. I would also loosen the bowl under the bottom fuel filter and see if it is dirty or has water in it. Condensation from sitting can happen. There are 3 Longs in my family now.

It's a Model 560.

I'd start at where to fuel goes out of the tank,my 460 was starving for fuel problem was the fuel wouldn't come out the tank I finally just drilled up thru the outlet hole and opened up a place for the fuel to come out fine after that.