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mini excavator diesel engine looses power and sounds like its gonna blow up (video)

permaculturist · 2017-10-30 11:57

here is my mini ex in the spring before any engine issues: and here it is today, making a scary rattling noise: this started after I was working the mini ex hard for a few hours loading compost with fast 180° turns and it just died on me (probably from overheating) - the radiator needed some topping up, it seems some of the fluid leaked or boiled off. I haven't had any fluid loss after that, but the rattling seems to go louder each time I use it. right after the "compost incident": now the mini ex gets weaker and weaker every time I use it. at 70% throttle when extending the boom to full reach (empty) it is guaranteed to bog the engine down until it dies. I can only work at 100% throttle making very slow moves. Even traveling causes it to bog down unless I punch the throttle. Does anyone have any idea what could be the cause of this noise and loss of power? The nearest shop is so far away that it would be better if I remove the offending part and had that fixed (like I already did with the starter). or is the noise just a sign of a engine that has 6500 hours on it and I can continue working until it blows up years from now?

Replies10
  1. #1permaculturist2017-10-30 12:39

    and the machine itself is a Schaeff HR12 with a 3 cylinder engine: L3E 0.952L (google says its a Mitsubishi)

  2. #2200lc12017-10-30 13:31

    I can't say for sure but I'd suspect one of your three cylinders isn't doing it's job. Videos don't show exhaust, which would help indicate poor combustion. If it is a cylinder you can start by loosening the nut each of the injector lines, one at a time, at idle to see which one doesn't affect rpm, that would be your offending cylinder. If there was an obvious cylinder then I would look at the injector and valvetrain for any obvious failures. Next I'd do a compression test. It's kind of difficult to troubleshoot from a 5 second video, how it starts, idles, revs up, recovers under load, etc. Just some backyard ideas, I'm sure somebody that does it for a living will come up with some advice. Either way I'd figure it out before it eats itself. You might only have a fix at this point instead of an overhaul if continued to run.

  3. #3permaculturist2017-10-30 13:34

    when it starts up it puffs a lot of blackish grey smoke and when it runs it smokes way more than it used to I'll make a new, longer video when its less windy

  4. #4Tones2017-10-30 15:11

    It sounds like the top of a piston has come off. It's probably buggered and a throw away by now unfortunately. I would not run that engine, pull the injectors a get a camera into it. That will tell the story. ,

  5. #5permaculturist2017-10-30 23:31

    Tones : do you mean the whole engine is probably buggered or just the piston?

  6. #6Ronsii2017-10-30 23:40

    'If' the top of a piston came off the whole engine is probably gone Best thing you can do now is not run it any more until you can get a look inside the cylinders like Tones said... who knows you might find it to be something else....

  7. #7Tones2017-10-31 01:51

    That depends on the cost of repair against replacement. If it's done a piston then it would be safe to say the cylinder will be scored. If the top of the piston has come off it will have damaged the head. But I'm only guessing as you are, you need to look inside and determine what has gone and take it from there.

  8. #8jaytech2017-10-31 12:05

    have you seen these cameras on ebay? "Camera Inspection Endoscope Snake" they plug into phone and are less than 15 bucks

  9. #9permaculturist2017-10-31 16:48

    thanks, ordered one

  10. #10slodank2019-09-11 01:03

    Did you ever find out what the problem was? I have a light tower with the L3E engine making the exact same noise. Would like to know if you ended up fixing it and how. Thanks!