Help nissan 720 sd22 diesel

[waynosworld]

The diaphragm controls the fuel mixture, like the pedal controls the amount of air the engine gets and how much fuel it gets via the venturi which creates vacuum to pull against the spring using the diaphragm that is always trying to floor the injection pump, it is a balancing act.

I had to go thru the balancing act when I put a turbocharger on my SD25 engine with an inline injection pump, how does one put a turbocharger on a system with a venturi that creates vacuum that pulls the diaphragm back to the idle position, it has to have vacuum in a closed system that is under boost?

If your diaphragm had a tear in it that actually leaked the engine would likely be blowing mass amounts of black smoke out the exhaust, I am talking about clouds that more than likely would attract a lot of attention, and it would not be drivable, the engine would run away rpm wise if it can get air, mass amounts of black smoke and or high rpms, I have seen videos of this, no vacuum the injection pump is full rich, like it is floored, but the pedal is not floored, when the not running the injection pump is floored/full rich unless the injection pump controller is working properly and moves it to the fuel cutoff position, the internal spring puts it in that position, this is why people disconnect the injection pump controller that is not working properly and use a choke cable to cut the fuel off and shut the engine down.

If the engine idles normally when running, and it is not blowing out mass amounts of black smoke the diaphragm is likely not leaking, or leaking enough to cause an issue.