Home>> Battlefield>> Use Your Own Head or a Sad Bubble Story>>
InsaneHydraulics - Sergiy Sydorenko 2009-2010 All Ridghts Reserved
Home
Introduction
The Simple Test
Back-Engineering?
The Most Basic Basics
Let's Talk Hydraulics
Back-Engineer This!
Battlefield
Kaboom
Library
News Archive
Bla-Blaimer
Contacts
Guestbook
HomeIntroductionThe Simple TestBack-Engineering?The Most Basic BasicsLet's Talk HydraulicsBack-Engineer This!BattlefieldKaboomLibraryNews ArchiveBla-BlaimerContactsGuestbook |
      I must say I was quite uncertain about where to place this article, or better, this sad tale of mine. Finally I decided to put it in the Battlefield section as it was, in fact, a lost battle.

      This story may not be directly related to oil hydraulics, but is a perfect example of how it's important to use your OWN head  while troubleshooting a failure, instead of blindly following an "expert's" opinion. Don't get me wrong here, I am not against the "expert", I am against the "blindly".

     Some three years ago I was very happy to present my wife, who had recently (finally) gotten her drivers license, with a "brand new" 1995 Peugeuot 306 with a generous 1.8 liter turbocharged intercoolled diesel engine with mechanical fuel injection, the feature which alone was more than enough to convince me into buying the vehicle (the presence of the Bosch piston fuel injecting pump was filling me with warm  feelings...) The car cost 2k eur, which seemed quite a bargain at the time as the automobile was equipped with air conditioning, power steering, electric windows, mirrors, central lock, radio, etc...

      For about a week I was delirious with joy at the car. Then the perfectionist inside took over and the nightmare started... Yes, yes, I am one of those unfortunate guys who seek explanation to anything around them that is not yet explained, and are unexplainably compelled  to make everything work "the way it is supposed to". Like when my new Vista armed computer (few days after the infamous Vista launch and crash) went gu-gu and refused to accept USB memory pens by freezing whenever a memory pen was inserted, it became impossible for me to work even when I was not using any pen. The itching feeling of incomplete functionality was there... driving me crazy, demanding fixing and causing my Microsoft Gates related vocabulary to expand every day... 

     Anyway, the machine was running perfect except for the fact that every now and then the motor seemed to loose power, like when I would accelerate, the acceleration rate would be kind of jerky, sometimes the car would just leap forward like a muscle car, and sometimes it would feel like I wasn't accelerating at all, although I was pedaling to the floor. Another symptom was the inability to maintain steady speed while cruising, there were always small, almost imperceptible jerks present. My foot wouldn't change the position and yet I could feel the car to accelerate and decelerate on its own. My wife didn't see it as a problem, and indeed it was almost not noticeable, but the problem WAS there and it was demanding, no, CRYING FOR a solution. All the joy of driving had been sadly gone...

     Confident it was fuel related problem I went to my car mechanic to see if he could take a look. Unfortunately my good friend had left for Angola and I dealt with an employee of his, who inspired confidence with many years of experience and lots of Grey hair... As soon as I related the problem he said: Don't you worry, my good sir, it's the injector pump problem, we will repair it and it's gonna be all right! A week later I went to the shop to pick up the car. "Does it run smooth?" -  I asked - "Like a missile" - said the mechanics. The bill showed that the car, besides the injection pump repair also got new fuel and air filter, which seemed logical, so I went home happy. First miles, however, showed that "the missile" kept on missiling in the same jerky manner it had done before. Pretty sad I called the shop and arranged for another visit.

     "Don't you worry, we'll replace the injection pump, the one you have is, unfortunately, damaged beyond repair." - said the mechanic.  Although the price of the new injector pump was a little high, It was a matter of principle for me, so I gave it a go. A week later I went to the shop to pick up the car. "Does it run smooth?" - I asked - "Like a jet fighter" - said the mechanics. A quick glance under the hood revealed a "new used" Lucas injector. The bill showed, besides the fuel injection pump, an original intercooler air duct. "Just in case" - explained "the artist", so I went home happy. First miles, however, showed that the "jet fighter" was jetting in the same freakin' jerky way. Pissed off, I called the shop and arranged for another visit.

     "Looks like we've got ourselves a tuff one here" - said the mechanic - "don't you worry, we'll replace the turbo charger, and it's gonna be all right!" When I asked why the turbo, the answer was "well, there's not much left to replace, is there? It's got to be the turbo" Then I told him I had actually measured the air pressure inside the intercooler and it was not too different of what was considered normal, in fact, I asked him the correct pressure value, which he didn't know, and I am guessing, considered the question as an offence to his experienced self. "Anyway", he said, it's not a "normal" turbo, but a "volumetric" one, which is far more complicated and prone to malfunction". My wife, who had been presented with the car and hadn't driven it yet was beginning to worry, so I gave the new turbo a go. A week later I went to the shop to pick up the car. "Does it run smooth?" - asked I. "You wouldn't beleive it!" - said the mechanic - "like a rocket it does!!!" The bill showed the turbo charger and tons of labour, and some other shit I can't remeber. Well, it's life, thought I, and went home happy. First miles, however, proved that rocket science has a lot to achieve yet, as the "rocket" was rocketing in THE SAME F@CKING JERKY WAY as before. I didn't call the shop any more, I decided to pay a surprize visit one of the next days.

     Next time I showed myself in the workshop I could swear I heard the sound of a breaking glass and a person running away. I guess my facial expression and clenched hands had given me away... Or maybe the blood filled eyes...  Anyhow, the artist wasn't present, but there was an assistant of his, changing oil to some car, and he asked me what the matter was. Frustrated,  I shared with him my story, which surprised him a lot. Well, he said, I am no mechanic, but I do think it's fuel related, and the most probable explanation for the not linear fuel delivery would be air bubbles inside the fuel line. You see, he kept on, on this car there's no auxiliary pump inside the fuel tank, so the injector pump creates depression inside the suction line and if you have even the smallest opening to the atmosphere along the fuel line, air gets sucked in, air bubbles are formed, and there you go - the jerky engine work, especially on high regimes during acceleration. Besides the most probable cause, it's also the easiest to confirm, all you need to do is install a transparent piece of hose in the admission line of the fuel pump and check for air bubbles. But since you're here, lets take a look at the fuel filter assembly, as it's the part that gets tampered with the most. Stumbled, I didn't utter a word and watched the man open the filter. It turned out that underneath the filter, in the bottom of the assembly, there was a small plug (water draining?) which had a suspiciously dry and dead stiff o'ring seal. After 2 minutes spent replacing the o'ring and closing the filter the problem was gone... GONE for good!!!  For the first time in my life I felt like kissing another man. (please don't use this phrase out of the context)

     Then came the feeling of enormous shame. I, more then anyone, should have thought about air entering the suction line of a pump. I am the one who has used transparent hoses for air detection. I am the one who has always defended independent troubleshooting. I am tired of seeing oil leaks or air entering hydraulic systems through faulty o'ring seals... The list goes on...

      My brain just got frozen completely by the fact that I was dealing with the area beyond my expertise, so I completely surrendered myself to an opinion without questioning it. I have absolutely no excuse and the whole expense I suffered (doubling the initial price of the car) served me a lesson to be never forgotten.

    The point here is that even the most experienced experts mistake. Don't be afraid to ask questions when you see something you don't understand, there's no shame in it. Whenever in a troubleshooting situation, look for educating yourself about the subject. Don't surrender yourself to an expert's opinion BLINDLY, seek for logical explanation or ask him for one. In my example my dumbness and mind's inertia cost me two times the initial price of a used car. In case of a hydraulics machine, an incorrect or illogical  troubleshooting technique may easily cost as much as several NEW cars and tons of labor. Make your own conclusions. As for me, I find my inner piece considering this predicament as a piece of education I paid for.

P.S. No need to say that my Vista expanded Microsoft related vocabulary was used by me ON me for at least a month after the o'ring change.