Low fuel pressure gen 4. 2200 engine
I have a problem with fuel pressure suddenly dropped to zero than after using the electric pump it increased to 0,17 bar, I changed the fuel filter and then the pressure increased to normal 0,29 bar. last trip it suddenly again droppet to zero and after using electric pump the pressure returned to 0,13 bar. Electric pump located before the fuel filter. have checked the fuel flow by disconnecting supply line to mechanical pump and flow is Ok 45 ltr. pr. hour. the fuel pressure from electric pump is 0,20 bar. Any idea what could course this problem? Could it be something with the mechanical pump?
It could be be something with the mechanical pump. You could disassemble the mechanical pump and make sure there isn't any dirt on the valves. I guess your fuel pressure sensor is located between the mechanical pump and the carburetor? The only other options is that there is some kind of partial blockage in the lines.
correct, pressure sensor is located between mechanical pump an carburettor, I will disassemble the pump and look at valves and the diaphragm.
i have checked the valves for dirt and the diagram for holes. No problem there. Still not more than 0,2 bar. Flow from tank before pump is 42 ltr. Pr hour. Any other thing to check?
The only other thing to check is that the plastic spacer where the pump mounts to the engine, can get squashed. Check that it combined with the gaskets is about 6.5mm.
Other than that all I can think to check is that there is no small leak where it can suck air when the electric pump is off.
The final test is to try another fuel pump.....