Full de-mandate on a 15 litre Cummins

[mikkhh]

I attained four day course on heavy equipment diagnostics and service at a trade school that teaches that kind of stuff. I was dissapointed to say at least..

During the lecture part I mentioned things talked about here, for what is EGR used (it is not "reburning" exhaust gas !!!) for, what is the difference between cdi, pcci, hcci. At least the lecturer did not argue with me about those things at all and looked like he seemed to grasp things. Until came the workshop part of the class. There was no diagnostic scan tool at that trade school. Well actually, there was but they had no idea how to use it and therefore did not show us.

The lecturer was telling how good were the machines that are now 30-50 years old, I told that as a hobby or leisure project yes you can play with them, but if you have to work and earn a living, hard to break the news but for that usage scenario these machines belong to the scrap yard especially due to high costs of fuel, low power, hard to get quality parts, old parts are remanufactured countless times already and are not lasting. New original parts for old machines are not made anymore, aftermarket parts for 30-50 year old equipment around here are total garbage.


Few weeks ago I spoke with the guy who works at Paccar training dealership mechanics. He told that it is quite sad how undertrained dealership mechanics are and people just do not care. Oh well, he kept telling that in Russia and at developing countries there are exact same trucks/engines that in the US, AUS, Europe, but those do not have any emissions or any EGR (no DPF, SCR I absolutely believe, EGR highly doubt, even Toyota Hilux meant for "no emissions" countries still has DOC and EGR). Next time I see him I will bring up the topic of Paccar PX-9 engine, maybe even show him software parameters, maps and stuff for review in plain english text file. Engine wise talking mentioned him about crankshafts getting bent, main caps getting distorted if you take way more power out of an engine than it is designed for. Well reply was, that good engine builder knows and can sort out stuff so reliability is not a problem. There are physical limits out there and exceeding the factory power output by 2-3 times will come with huge costs reliability wise. The problem is quite grandiose - most people fixing things do not have a genuine interest and also lack pride in their workmanship and are too ignorant to learn how things exactly work, on the other hand most people training others are usually doing that because they lack the competence to work on that field. There is lack of instructors and teachers therefore it is easy to find job.

Not everybody is like that, but the majority is that way. Actually there has been somebody who for the almost last 15 years has talked on forums about how to get a truck engine running properly, how to keep dpf, egr systems running healthy, what to look for deletes to ensure proper engine life and reliability, the same person has also hanged around on those "tuning" sites (where people messing up ecm software usually hang) trying to educate and promote discussion, but has been banned on almost every trucking or tuning related forum for some reason. The amount of bad information out there is enormous, to make matters worse the amount if ignorant people thinking that they know everything and are not willing to accept by any means that they may be wrong is also enormous. Some people refuse to learn after repeated failures and just keep on blaming others - modern engines are weak, materials soft and so on. Lots of people are ignorant and refuse to read the manual and even when they read they fail to apply things listed there especially when talking engine rebuilds.


When talking about mandate´d most of those so called experts on ecm tuning believe that by eliminating bunch of fault codes is the way how (BAD) deletes are done. Most have zero clue about engine mode selection, mandatory timing changes to ensure longevity, controlling the turbocharger. Most tell that they have done loads and loads, engines run more than million miles without any issues. In reality if exhaust is emptied for proper flow and no heat traps + egr is blanked physically then the boost levels are too high for engine operating now. At idle diesel does not need boost, most bad deletes are overspooling the turbocharger.

What is more the usual driver, just wants to get rid of the CEL and does not care about reliability. It is hard to explain to some fleet owner that you MUST clean sensors yearly, bake the cans every two years, clean egr piping and cooler. Even though this maintenance helps to lower fuel consumption, the amount of downtime due to all kinds of aftertreatment issues as you see proper maintenance is cheaper in the long run than dealing with the aftermath.