No Pressure at Bleeder but Intank pump works

[Kalashnikov]

I was driving my Deuce and it had a severe lack of power and would keep cutting out like it was staving for fuel especially when I shifted into 4th. I figured it was the filters again. So I changed out all the filters and went to bleed the system but I hardly get any pressure at the bleeder. Sometimes a little fuel will dribble but then it stops.

I thought maybe the bottom of the fuel pump fell off since it sounded like it was either clogged or had no load. Nope, all together. I tested it and it pumps fuel.

I figured I had a clogged line so I blew air from where the flex and copper line meet right under the IP back to the line that connects to the intank pump. Still no pressure when I reconnected the lines. Then I disconnected the line that goes to the injectors from the IP and blew back to the flex hose. Cracked the bleeder and I could hear air coming out. I reconnected the lines and still no pressure.

I read 3 to 5 PSI for the intank pump. I haven't actually tested the pressure but I know it's flowing up to that flex line. It seems like it has good flow too.

The fuel I started with was WMO/Hydraulic oil but I drained most of it and threw in some 2 stroke mix so I know the viscosity isn't the issue anymore.

Now I'm not sure what to test. I'd like to get it going this weekend since it'd suppose to be nice out and I haven't driven it for like a month.

 

[doghead]

Have you been draining your filter housings regularly BEFORE the winter (freezing) weather arrived?

 

[Kalashnikov]

Every once in a while but there wasn't any water. I stared at the beginning of the month when it was still above freezing so there isn't water frozen in the lines if that's what you're thinking.

 

[Warthog]

Remove the flexible line that comes from the primary filter attaches to the fuel pump on the injector pump and test for flow. Item #20

There is an additional pump on the side on the injector pump. Inside this pump is a preassure relief valve. I have seen them stick

You can also disconnect the return line on the secondary filters and blow the lines out Item #19

 

[Heavysteven]

I would flush the system with new diesel and injector cleaner first, second check/pull tank pump, and if that fails start trouble shooting the injector pump.

 

[m-35tom]

So I changed out all the filters and went to bleed the system but I hardly get any pressure at the bleeder. Sometimes a little fuel will dribble but then it stops.


when you remove, not open, the bleeder from the filter assy, you will get a fountain of fuel with the tank pump. without this you cannot bleed the system. just because your tank pump sounds like it's running does not mean it's pumping.

what you described is classic restricted fuel flow.

tom

 

[Kalashnikov]

It was the return lines. I disconnected #19 in the diagram and blew it out. Got fuel out of the bleeder after. Thanks for the diagram Warthog and everyone else for your help. I'm going to treat all my fuel with injector/fuel system cleaner from now on instead of once in a while and filter a little better which I already knew was an issue.

 

[Warthog]

Glad I could help out and congrats on getting it figured out.