Doosan dx140lc track problem

[Flashgord]

Hi everyone, this is my first post. I'm looking for some help solving a problem with the tracks on my doosan dx140lc. Il start by saying I've been an operator for a couple years but I am not a fitter and not very clued up on the mechanical side.

the issue I have is - when tracking, particularly in the faster speed, the machine seems to build a 'bouncing' rythem, it's unbearable and bounces the whole machine, can't be good for it and sounds awful and shakes me to bits. We do have to track on the road quite a lot on site but the problem seems just as bad when tracking on earth or stone etc.

ive pumped Grease into the tracks as hard as I can possibly squeeze! And when I jack the machine up the tracks don't sag more than a foot. I'd love to hear anyone's thoughts and tips on this.

many thanks in advance for all your help.

here is some info on the machine. It's about 2010, 2500 hours
lastly it might be worth mentioning that due to the time of year the tracks do get very full of slop and earth.

[Muz]

Hi and welcome ... They shouldn't sag that much for a 14 tonner ,your chains may be well worn..or have a problem with the tensioners Where are you using it?

[ianoz]

Yep , with Muz on this one Should only be a couple of inches sag max .It sounds like the Adjuster has reached its limit .At 2500 hours I would not have thought the tracks would have that much wear But the traveling in high speed a lot could create more wear .Or possibly something has jammed the adjuster stopping it going forward .See if you can put up a photo of the Idler possition on the track frame .If it is close to the front of the trackframe .It will be out of adjustment .

[Flashgord]

Many thanks

Yep , with Muz on this one Should only be a couple of inches sag max .It sounds like the Adjuster has reached its limit .At 2500 hours I would not have thought the tracks would have that much wear But the traveling in high speed a lot could create more wear .Or possibly something has jammed the adjuster stopping it going forward .See if you can put up a photo of the Idler possition on the track frame .If it is close to the front of the trackframe .It will be out of adjustment .

Hi thanks for your reply. Ok I thought I'd update with a little info, I've checked both tracks today and both are good and slack is about 2 inches Max, the idler still has room for adjustment. I am going to try and upload a picture and also a video from inside the cab to show how bad the 'bouncing' is. If anyone knows how to upload videos!?

thanks again for your replies

[ianoz]

Easyest way to upload a Video ,Is to upload it on to You tube and link it to here
But if the Tracks are adjusted right ,as it sounds like they are.Maybe it isjust something that machine does . I would try at different revs , see if there is a sweet spot that it runs at ..
Other than that it still got the carrier roller ?Our old 20ton hitachi did a carrier roller so pulled it off and used the machine till we got another one I think i remember the track bouncing with out it on .

[Muz]

Yes cos the chain will catch on the frame if that roller is missing. The other reason could be if someone has taken a link out of the chain to shorten it, this will throw out the pitch for the number of teeth on the sprocket and give you the same effect

[James Waterfall]

Hi thanks for your reply. Ok I thought I'd update with a little info, I've checked both tracks today and both are good and slack is about 2 inches Max, the idler still has room for adjustment. I am going to try and upload a picture and also a video from inside the cab to show how bad the 'bouncing' is. If anyone knows how to upload videos!?

thanks again for your replies

Slacken your tracks off a bit again or your going to ruin your chains and top idlers fairly quickly. What happens if you cast the stick away while tracking or turn the house to one side or the other? It's a balance issue that causes the hop. A lot of machines suffer from it with the boom up and stick in close. Just one other side note. Fast tracking on a hard surfaces is a killer. Maybe your not paying the bills? but at a guess it would probably be doubling up your wear and tear.

[Richie jones]

Track problem

All of the above is true but if you spend that much time on roads and chippings put rubber block on your tracks this should ease your rough ride and keep it in intermittent travel mode

[v8druid]

I know very little of tracked machines but would guess it's a 'Question of Balance', to quote the Moody Blues and she's nodding, as a duck will.....try tracking about with your boom/dipper in differing locations.