ESP Filling: How to Fill Your ESP

Hello everyone,

While considering how to inject more fuel without extending the injection time, I came to the following conclusion.

If you install a small booster pump before the diesel filter (it must, of course, provide enough pressure so that the pump doesn't need to draw fuel),...
If a larger diesel filter (to reduce pressure loss) is installed, the high-pressure chamber in the ESP would need to fill more quickly, which would also increase the injection quantity.

To ensure that the fuel injection quantity remains consistent, even if the piston deviates slightly from its intended path, the higher injection pressure forces the fuel into the cylinder, maintaining the same injection duration.

This would also have the advantage of better fuel atomization.

The additional booster pump and larger filter will definitely result in lower pressure losses.

What do you think about the idea?

tim27 wrote:

What do you think about the idea?

Hi Tim,

Your adjustments would be in the low-pressure section, which, in my opinion, wouldn't make a noticeable difference.

The real bottlenecks are in the high-pressure section, mainly the nozzles, which are crucial for ensuring a high injection pressure and thus good atomization.

That's where you need to start if you want to noticeably increase the amount of diesel injected into the cylinder without using electronic controls, for example, using KW tuning nozzles.
Of course, they are illegal, as I was subtly informed when I inquired.

Deleted upon request.

While considering how to inject more fuel without extending the injection time, I came to the following conclusion.

(...)

What do you think about the idea?

Let me think about it...

Depending on the speed, the pressure inside the pump chamber ranges from approximately 4 to a maximum of 12 bar. The pressure should not exceed 12 bar, otherwise seals and other components may be damaged or the housing may burst.

The injection pressure is approximately 850-900 bar at rated speed. Let's say you manage to increase the internal pressure by 2 bar... do you think that, given the compressibility of diesel, only about half as much diesel will significantly enter the high-pressure chamber?

'For that, you need to adjust the initial injection timing. This is because it's directly dependent on the internal pressure. The adjustment piston is acted upon by pressure proportional to the engine speed, and the control valve usually only makes minor corrections. If you artificially increase the internal pressure, this control loop will completely fail...'

Conclusion: Logically sound, but difficult to implement with liquids. It would likely be more successful in pneumatics.

CU Gremlin.

*)
Has anyone ever considered the possibility that a worn fuel injector control piston or its spring might be contributing to cold start problems?

Hi,
The high-pressure chamber in the ESP has a duration of less than 1/10, or even greater than 1/100, of a second.
If the high-pressure chamber is not completely filled because there is insufficient time for it to fill, reducing the suction power (pressure losses) – ideally to zero – will make more pressure available to fill the high-pressure chamber. Consequently, even with the same injection time, more fuel can be injected. Increasing the injection quantity with the same injection time logically increases the injection pressure, which leads to better atomization of the fuel.


I'm going to install a larger diesel filter to test whether the theory is correct.