Real time help: Fuel starvation (1 Viewer)

[rideglobally]

I am currently in Senegal traveling with my 1980 hj47 with 12ht engine. My engine shuts down due to fuel starvation. When I bleed the sys you can hear air coming out when I open the bleed valve. So there is pressure. The engine starts no problem after blending then will run again for about 10 mile then will shutdown again due to fuel starvation.
My plan is to replace all my fuel filters and check all fuel lines for leak. I am wondering if there is another reason, for example do you think there is an issue with the lift pump or another? Thank you @cruiserpilot

 

[duncanrm]

The factory sedimenter, mounted to the chassis rail behind the vacuum tank is a common source of fuel delivery issues on HJ47s.. my first step is almost always bypassing this. A few images of the sedimenter can be found here. HJ60 Sedimenter - https://photos.app.goo.gl/yTBd1qwecH7oP5L77

 

[rideglobally]

The factory sedimenter, mounted to the chassis rail behind the vacuum tank is a common source of fuel delivery issues on HJ47s.. my first step is almost always bypassing this. A few images of the sedimenter can be found here. HJ60 Sedimenter - https://photos.app.goo.gl/yTBd1qwecH7oP5L77

I took the Sedimenter out a long time ago what i have now is a racor filter with and water separator. I have been using 20 micron but could not find it here, i am now using 10 micron. I will be changing all the filter today and check all lines. I did realize that at low speed, low rpm the engine has no problem, we drove through 100 km of wash board and very bumpy road no issues. So i think there is a restriction at the oem filter but i don’t understand why there is a lot of air that accumulate at the bleed valve, you can hear the air with pressure coming out when you open the bleed valve. Thank you.

 

[relaxedcruiser]

Interesting - if you can bleed air - that air must enter somewhere between the fuel level in the tank and the bleed point. Maybe a pinhole in the fuel pickup tube at the tank ? If the fuel pickup screen inside the tank is partially blocked - that would help sucking air into the system at a weak spot too...
Not sure how it looks on the 47 (if you still have the original setup) But right there where the pickup is accumulates a lot of dirt and enhances corrosion.
Just a thought - after bleeding - pressurize the fuel line backwards with air and you could probably see or hear where it leaks. Don't use all the available 10 bar .... just enough to check. Sometime air enters but diesel doesn't leak necessarily at that very spot.
I hope you have a good spot to check it all out.

 

[Squash]

Imagine sucking on a good straw. Now try sucking on a straw with a hole in it.
Your fuel system is sort of the same. Find the vacuum leak. If possible try using a section of clear hose. Bubbles in the line indicate a vacuum leak. Double check the Racor threads use fuel compatible thread tape.
Another way is to feed your pump via a clean container of fuel to bypass any suspected problem area, and then fix the suspect.
Be methodical, start at the pump intake and work your way towards the tank.
If you suspect blockage due to dirty fuel then try filtering out via cloth, decanting, and for what it's worth making certain not to get fuel from the top of a barrel( light crap floats) or the very bottom where muck and water reside. This is where a filter with a decent sized glass bowl really helps. The above absolutely helps when you are fuelling helicopters or aircraft from barrels in the Arctic and you have no idea how long the barrels have been sitting.

 

[rideglobally]

Thank everyone blockage found. It was the small filter before my electric fuel pump. I re located the electric fuel pump (not oem) after the razor filter and took the electric fuel pump filter out. I have three filters now only two, less restriction.