Piping return into pump

[Jameswallace]

I seem to have a quite rough idle on veg - i know veg is thicker etc, but I have a pre heater, so my engine, and fuel lines are 70 degrees hot, so no excuse really, it will run rough as anything if I dont rev the engine, often stalling. Even when the temp gauge is 3/4 up to the middle position (normal running temp)

Would putting a Y peice into the the intake for the fuel and piping the return into this possibly help? It sounds like air is present, but I know it isnt air, I have checked many times with a clear pipe, and tried another IP

I was thinking, it would reduce the amount of 'sucking' the IP wouod have to do in order to get fuel, especially on idle... Or would this cause problems for the pump?

Thanks

[budweiser]

how about get a spare fuel tank with pure diesel, and a switch over valve to start and stop the engine with diesel, not the other stuff that can get cold in some places causing problems

https://www.oilybits.com/pollak-6-po.../prod_390.html

[Jameswallace]

I used to do that, those valves are quite restricting on the fuel flow. When i removed them i had more power! also the lost boot space was annoying,

I have definitly taken a step forward moving away from those, but thanks for the suggestion none the less

Also, not sure i can use cold as an excuse, as I have 3 metres worth of fuel line at 70 degrees, and a hot engine when i start in the morning. It runs a dream until the glow plugs go out (if run from dead cold) whereas when its warm they go straight out as its 'warm'