M1009 opinions before IP change

[ms1223]

My 84 M1009 will start run for a couple of miles loose power and stall. I checked the fuel for water, new fuel filter, checked for air leakage and cleaned the return line check valve a couple of times. Fuel pump pressure is good.
Any suggestions before I go after the IP? It seems to run good after it stalls only for a few minutes. Does the return line check valve go bad?
Any suggestions welcomed.
Thanks, Mike

 

[Ken_86gt]

Was the check ball dirty enough to require cleaning? If so, you either repair the fuel pump or remove the check ball....For long term reliability I would look into the fuel pump.

 

[ms1223]

Thank, I'll try removing the ball check and see how it runs

 

[Barrman]

Was there junk inside the return valve? If not, there is no reason to remove the ball.

 

[tequilaiam]

How do you know if there is air leakage?

My experience: possible that air gets in but fuel doesn't drip out, making it impossible to source a leak. I bought clear fuel line and quickly IDed where the leak was comming from.

Check your water in fuel sensor in your fuel filter assembly. I found mine had a tiny pinhole leak that sealed up when pressurized by the pump but let in a little bit of air to allow the filter housing to drain back to the tank. therefore, I could start it up then after a little while that air bubble got sucked into the IP and stalled it.

 

[ms1223]

Thanks for the info. When I cleaned the ball check it had a small amount of small hard particles. I put a clear hose on the retun line and saw no air bubbles. Fuel is good pressure. The truck will run good for ten minutes after sitting for a few hours. It then stalls, has no power, it will restart immediately. It will stall when slowing down, it's a real treat when you restart with you your foot on the brake trying to slow the truck

 

[Barrman]

If you had particles in the check valve, your IP is coming apart. Start planning for a replacement or rebuild. The stalling while coasting is another sign of it dying.