I started my B7500 this morning, drove it about 50' and it died as if it had run out of fuel. I tried to restart it but it would not even try to fire. The B7500 doesn't have the electrical interlocks so all it needs is fuel and air to run. 
I checked the obvious stuff first. It had about 1/2 tank of fuel. I pulled the fuel filter but didn't find anything wrong there either. The air filter was OK also.
Sooo .... I pulled the fuel line at the lift pump and had fuel there. At this point I had to remove the hood and air filter housing to get at the rest of the fuel system. I checked the vacuum at the air filter hose and had plenty so it was getting air but it still wouldn't fire.
After a bit more checking I noticed a little bit of fuel on top of the fuel pump. I pulled off the return hose that comes from the injectors and found a very small split (maybe 1/8" long) in it. I replaced the return hose and bled the air out of the injectors. That solved the problem!!!
Apparently that very small split in the return hose (left of the pump in the attached picture) was allowing it to suck in just enough air to stop the high pressure pump from working. Maybe this will save someone else a couple hours of fooling around!
I checked the obvious stuff first. It had about 1/2 tank of fuel. I pulled the fuel filter but didn't find anything wrong there either. The air filter was OK also.
Sooo .... I pulled the fuel line at the lift pump and had fuel there. At this point I had to remove the hood and air filter housing to get at the rest of the fuel system. I checked the vacuum at the air filter hose and had plenty so it was getting air but it still wouldn't fire.
After a bit more checking I noticed a little bit of fuel on top of the fuel pump. I pulled off the return hose that comes from the injectors and found a very small split (maybe 1/8" long) in it. I replaced the return hose and bled the air out of the injectors. That solved the problem!!!
Apparently that very small split in the return hose (left of the pump in the attached picture) was allowing it to suck in just enough air to stop the high pressure pump from working. Maybe this will save someone else a couple hours of fooling around!
