Fuel Flow Back

[gregvass]

I have a 73 AM General 5 ton with the cummins 250. When I leave the vehicle sit for 24 hours the fuel flows back into the tank causing me to turn the engine for ever to pump the fuel back to the injectors. What could be the cause. A bad injector, loss of vaccum somewhere?? Also when idoling it will attempt to die and upon acceleration it acts like it is slow to until rpms are up. HELP!!

 

[Andyrv6av8r]

You have an air leak in your fuel system. Pressurize your tank and look for it.

 

[pctrans]

A common place for the air leak is the fuel tank switch valve located under the driver-side floor panel. The hose connections to the valve assembly are notorious for cracking. Removing the toolbox under the driver door gives you good access and room to work.

 

[EMD567]

Also check the flexible line from the fuel filter to the IP. It can crack, and suck air. Ask me how I know............