CRAZY priming question

adammsmith · Mar 9, 2009

I posted earlier but seam to have a new problem. (recap) I ran it out of fuel and then replaced the filter. I primed it and it starts up just fine but looses power. Sometime it runs for 30 secs sometime 10 min.
Everytime it looses power, I bleed it at the injector pump and there is air there. I bleed it, the darn thing runs, then dies. I crack the bleed screw and air comes out. I then drained the tank to looked for any type of debris.(nothing) Next I ran a line from the tank directly to the injector pump. It started up then died. I cracked the bleed screw(at the injector pump) and it had air in it. I removed the banjo bolt and removed the copper washers. They were pretty worn. I filed them flat (as close as I can get them) ( they still have a groove). I plan to order new ones tommorow, could this be my problem? I can't see how air can be getting past them. I need your suggestions before I pull the rest of my hair out. thanks, Adam

HoyeTractor · Mar 9, 2009

Have you tried to run it with the fuel cap off or loose? I know that some models require a screen that goes right under the cap which has a tiny hole in it that vents the tank. Without that screen they will create a negative pressure in the tank. This can do weird things to the pump like cause the engine to die & then suck air in from somewhere. It sounds to me like it could be a possible fuel starvation issue.

Aaron
Parts@HoyeTractor.com
(940)592-0181

DieselPower · Mar 9, 2009

If it keeps getting air in it you possibly have a leak somehwere. Basically it's sucking air into the fuel line. Check your lines from the fuel pump to the tank. If the fuel tank does not draw from a fitting on the bottom of the tank then it has a suction tube, make sure it isn't cracked and sucking air.

Willl · Mar 9, 2009

adammsmith said:
replaced the filter.

Like DP said, your sucking air.
I'd recheck that filter base for starters.

adammsmith · Mar 10, 2009

I replaced the fuel lines the other day. I have a fitting on the bottom of my tank(so no suction). I will try to start it with the cap off as soon as it gets light outside. Thanks for the help and keep the suggestions going. I took the cap off. that doesn't seem to change anything. I will say it runs longer, stronger when the engine is cool. As soon as it heats up ,it bleeds just as much air out of the bleed screw, but doesn't run as long or as strong. It is wierd that non of this happen until I ran it out of fuel. thanks, Adam

Mike B in Boise · Mar 10, 2009

i am having the same type of problem i have an 86 ford 1700 after running it low on oil i changed the oil filter fule filter anf had to change the therast. it will run for a short time sounds loud but then it losess power and dies and will not start till it cools. help;

adammsmith · Mar 10, 2009

Thats funny. I can dig three post holes and then loose power and have to rebleed.

nostep · Mar 10, 2009

Did you think to run it from a small can of fuel with a fuel hose in it? That would eliminate all your fuel lines and tank as suspect parts. You can also try to pressurize the inlet fuel line with air pressure (between tank and pump) and see if there any leaks. 10 psi might tell you a lot. Just thinking out loud.

adammsmith · Mar 10, 2009

I will try those ideas tommorow. Thank you very much.

Underwaterdog · Mar 11, 2009

It sounds a lot like the problem tallyho08 was having a while back. He even had the injector pump rebuilt to no avial. I think he worked something around it with a air bleed line. The thread is a long read but there is a lot of information in it. Here is the link:
Yanmar loses power, slows down & kills