Diesel Injector adjustment - Is this real?

[veggie]

At the 14 second point in this video the fellow seems to be adjusting the injector pressure while the engine is running. Like playing with a carburetor mixture screw.
Is this really a "thing" with diesels.
If so, what is he trying to achieve? How does one know when it's "right" ?

https://www.youtube.com/watch?v=vQTkSelkXP0

[playdiesel]

Just another of 1000s of clueless people playing expert on YouTube No matter the subject.
An experianced person can get the injector pop off pressure close by eye and ear when on a test stand and then open the gauge port to set it right. Like any other engine spec there are good reasons for the manufacturer to place pop off at a certain pressure and it certainly cannot be done on a engine, running or not.

[Tom Reed]

However, OEM pop off pressures are based on clean diesel. If running something else, a different pressure may work better. If you have a pop off tester, try your hydraulic oil in that, otherwise what the youtuber is looking for is minimum fuel rack position under load.

This Dunn heavy oil engine looks like an interesting alternative for waste oils. https://www.smokstak.com/forum/attachments/the-dunn-heavy-oil-engine-pdf.513189/

[playdiesel]

Yes I own an injector setter and stand by my earlier statement. One can screw around with things he shouldn't and get away with it,, for a short while. I keep Lister CS pump cam lobes and lifters in stock for the guys that indiscriminatly crank up injector pop off pressures while playing with high viscosity waste fuels.
 If there is anyone around who has run high viscosity oils either new or reclaimed over a long period of time Im not aware of them. Lots if experimenters, hype and speculation but no long-term users. All successful WMO or WVO users that I am aware of thin the oils, either via heat or by blending but admittedly my knowledge is limited to shop customers and what I read here or on LEF.