Hitachi EX75UR-5

[Locofitter]

I misread the king post, was on the phone whilst reading the reply. We have a similar thing in my industry called king post which does a similar job thus was getting confused.
I thought it read 'connects the undercarriage to the upperstructure'.

Looking for information with regards to the track and bush issues. Is there a work around for the tracks and has anyone had any experience of making their own bushes or bushes made from Vesconite?

Ta

[v8druid]

I misread the king post, was on the phone whilst reading the reply. We have a similar thing in my industry called king post which does a similar job thus was getting confused.
I thought it read 'connects the undercarriage to the upperstructure'.

Looking for information with regards to the track and bush issues. Is there a work around for the tracks and has anyone had any experience of making their own bushes or bushes made from Vesconite?

Ta

Just been having a read on the Vesconite front ..... can't see it liking the forces exerted upon it by a digger's loadings? .... I'd either be turning up some EN10 bushes and having them induction hardened with soft (untreated) pins or the reverse, but the bushes'd be cheaper to get hardened

or

buy some stock Phosphor bronze thick wall tube and turn some bushes from that ..... I really don't think that your Vesconite is going to stick the pace



As for the track chains .... the tension doesn't sound hugely out, but I don't know a huge amount about them. The bushes and pins are obviously worn, probably internally and externally, thus increasing your effective pitch length .... but, at the same time, as the sprockets wear, their pitch centres will reduce, as the bushes wear deeper into the sprockets.

you say the sprockets aren't too bad ..... therefore the pitch of the chains can't be too bad either, so removing a link to get the tensioner and idler back into the sliders isn't going to be too drastic an action ..... when you reach the point that new chains are going to be needed, you'll replace the sprockets as a matter of course anyway ...... so nowt to lose really and tensioner improvements to be gained

Just how much tracking is this machine going to do? I'd also disconnect/disable the hi-speed tracking ........ kills tracks ... rapid

you could always get a quote to have them re-pinned and bushed too but depends on how worn the chain links are really

I have read somewhere that it's relatively normal to remove one link during the life of a chain, but if you get to the satge of having to repeat the process ..... they're probably well banjaxed by that point anyway.



AS for the slew 'slop' ..... measured at the end of an extended dipper, i'd say it's in fair condition .... there is bound to be wear at the pinion/ring gear interface ..... does it make any nasty noises?
pinion/ring gear fit is never solid / lacking any backlash/movement .... I'd be more concerned about checking slew ring lift ...... having a carbody/superstructure drop off'd be embarrassing
and don't over-grease the ring .... having grease oozing out of the seal is not good ..... grit and shit gets in by the same route, if the seal is bulging away from the mate face

[v8druid]

........, king post is crap

The principle is OK ..... just few people make 'em man enough to take any serious shit .... or at least the level to which I'd trust 'em to stick the pace and not wear out rapidly

[Nobody]

I misread the king post, was on the phone whilst reading the reply. We have a similar thing in my industry called king post which does a similar job thus was getting confused.
I thought it read 'connects the undercarriage to the upperstructure'.

Looking for information with regards to the track and bush issues. Is there a work around for the tracks and has anyone had any experience of making their own bushes or bushes made from Vesconite?

Ta

Could you supply a pic of the idling wheel so we can see how far out it is? Dont forget that you need a good amount of slack to get the track back on, so removing a link might be a bit drastic..
The track is also supposed to hang a little.. Rule of thumb is two fingers between tracks and most centered track roller

The principle is OK ..... just few people make 'em man enough to take any serious shit .... or at least the level to which I'd trust 'em to stick the pace and not wear out rapidly

Worst part about em is hinder of sight for me.. the much extended reach is very nice tho.

[v8druid]

Could you supply a pic of the idling wheel so we can see how far out it is? Dont forget that you need a good amount of slack to get the track back on, so removing a link might be a bit drastic..
The track is also supposed to hang a little.. Rule of thumb is two fingers between tracks and most centered track roller


Worst part about em is hinder of sight for me.. the much extended reach is very nice tho.

ain't gonna take a lot of tension to lose a few fingers sag then

[Locofitter]

Hi,

I will take a photo of the idler wheel when I am back there on Tuesday, the yoke pokes out roughly 20mm from the surround that it sits in, have 4 and a bit fingers slack on this track, dubious to adjust it as not sure how far the idler is safe to travel and wouldn't want to bend the track tensioning piston rod.

Vesconite is quite a new material and is used in many heavy engineering parts, diesel marine engines for a start (vastly bigger on load bearing than a 8t excavator). I would be happy to try this and feed back in a number of months as it does seem to be a very good option. Many people throw it out from the word go because they see it as plastic replacing their long loved metal bushes, which is fine. Many don't like change.
The machine isnt in daily operation, we mainly use it for lineside work. Have thought about disconnecting the high speed tracking foot switch but if I'm totally honest - its mainly used by a few old blokes who are so painfully slow to watch when in the seat, I doubt they ever use it. Nosebleeds if they go too fast

Slew makes no obvious noises, and has a little bit of play (maybe half inch) in the Z axis plane.

On the plus side, a manual has been sourced! All 1000+ pages which need to be taken out of many files and all put into searchable .PDF :/

[v8druid]

Hi,

I will take a photo of the idler wheel when I am back there on Tuesday, the yoke pokes out roughly 20mm from the surround that it sits in, have 4 and a bit fingers slack on this track, dubious to adjust it as not sure how far the idler is safe to travel and wouldn't want to bend the track tensioning piston rod.

Vesconite is quite a new material and is used in many heavy engineering parts, diesel marine engines for a start (vastly bigger on load bearing than a 8t excavator). I would be happy to try this and feed back in a number of months as it does seem to be a very good option. Many people throw it out from the word go because they see it as plastic replacing their long loved metal bushes, which is fine. Many don't like change.
The machine isnt in daily operation, we mainly use it for lineside work. Have thought about disconnecting the high speed tracking foot switch but if I'm totally honest - its mainly used by a few old blokes who are so painfully slow to watch when in the seat, I doubt they ever use it. Nosebleeds if they go too fast

Slew makes no obvious noises, and has a little bit of play (maybe half inch) in the Z axis plane.

On the plus side, a manual has been sourced! All 1000+ pages which need to be taken out of many files and all put into searchable .PDF :/

Now then .... "many a good tune played on an old fiddle" ... wise heads etc. !! ......."why run down , when we can stroll and **** 'em all" ...... if you don't know the joke ... PM me

1/2" play in the slew (ring)?? can you elaborate on that one?

Good news on the manual front at least and assume you mean that the idler carrier is presumably protruding 20mm from the frame ??

You must be up to the post count for pix by now mate

As for the vesconite ....... will be very interesting to see how it works out .... I'll try anything that works ... well

[Nobody]

Vesconite is quite a new material and is used in many heavy engineering parts, diesel marine engines for a start (vastly bigger on load bearing than a 8t excavator). I would be happy to try this and feed back in a number of months as it does seem to be a very good option. Many people throw it out from the word go because they see it as plastic replacing their long loved metal bushes, which is fine. Many don't like change.
The machine isnt in daily operation, we mainly use it for lineside work. Have thought about disconnecting the high speed tracking foot switch but if I'm totally honest - its mainly used by a few old blokes who are so painfully slow to watch when in the seat, I doubt they ever use it. Nosebleeds if they go too fast

I would very much like to see feedback on vesconite bushes if your set for doing that! Could get intresting

Had me laughing about them old blokes have a couple of em too.. One falls asleep while operating at times! Just continues the movement where he fell asleep when wakened like nothing happened

[Locofitter]

Indeed, the idler carrier protrudes approx 20mm from the frame. Is this an acceptable wear limit and will adding a bit of tension to this track cause damage to the idler/track tension ram?

With regards to Vesconite, I'm rather confident that it'll work. Haven't seen any bad reviews on it, see the link below for more information. I need to try and find bore/pin etc dimensions first.

http://www.oemoffhighway.com/product...vanced-polymer


As I am by no means an experienced operator, it would be nice to be able to get on a machine for a while to advance my operating competence. However, it seems the old blokes just shag the thing whilst me and a couple others end up repairing it.
Watching them use a grading bucket to dig rather solid ground and move lumps of hardcore was quite frustrating, given the bucket is a bit bent/twisted. Wouldn't mind but the ripping bucket was 50ft away!

Use the wrong tool for the job and you risk damaging your machine, seen it so many times in my field with other applications. Sad really.

[Muz]

Indeed, the idler carrier protrudes approx 20mm from the frame. Is this an acceptable wear limit and will adding a bit of tension to this track cause damage to the idler/track tension ram?

Its about as far out as Ive run any of mine, the piston for the tensioner will be quite far out of the cylinder at that point, but shouldnt bother it. The main issue with that level of wear is you are more likely to get tracks thrown off, so .. re bushing or re chaining reduces that likeliehood.

The last digger I owned with Nylon bushes (or similar) was a Hitachi EX8 ..micro .. and those bushes were crap IMO. I had no end of bother with it, and swore never to own another like it. I dont know if they just hadnt got the matarial right at that stage, but when you start getting site debris in about the system, it didnt seem to work. At least with greasers, you keep a constant pressure on the joint, pushing the shit outwards all the time.

[Locofitter]

I've been given a brief report on the dipper ram: not looking good although it is repairable.
It appears that the rod had bent with the dipper fully extended, this had dug the piston into the barrel. Fine, BUT... The machine was used for an hour or so after this which in turn has caused quite severe gouging to the barrel walls. End cap was also bent and has had to be machined off.
Wouldn't mind going to the engineering firm to see them repair it, do like a bit of machining myself.

Muz, is it a safe assumption to say that its probably better to take a link out? Or shall I see how far out the carrier comes once track has been adjusted to its correct tension and then make a decision based on that? The safer option, I think, would be to take a link out as at least this would buy us some time to be able to try and source track chains with the metal/rubber shoes.
This Vesconite is a material far stronger and wear resistant than Nylon, as said before its going to be a long time before we put those bushes in but when we do, i'll most certainly update this thread.
If its of any other interest, i'll also update with the ongoing overhaul of said machine.

The manual is ok, one of the ones that came on CD from the states. However, its a bloody ball ache trying to go through it as all the pages are hidden in so many different file folders. Trying to make it so its a single, searchable .PDF atm. Not having much luck with that either at the moment.
Its nice to have the schematics though, not all too familiar with hydraulic diagrams so this shall be interesting.

[Muz]

As a rule .. the further out the idler assembly appears from the frame the more wear it will exert on the frame that holds it,from a leverage point of view,as it is not properly supported, and it will give greater slap from side to side, leading to a much higher likeliehood of a throwm track, so either way, you shouldnt really be able to see the idler assembly. Cutting off a link just prolongs the inevitable, and is only a stop gap solution, but if funds are tight, it works for some, personally Ive never done it for the reasons mentioned earlier.

[Muz]

How does it change the pitch Muz Pin centres remain the same .

Hmm ? just re-quoted a dealer of old, without thinking about it .. perhaps thats only relative to systems that had sprockets at either end like some old 803's I came across .. but .. if one sprocket was an idler it shouldn't ? got me thinking now as to what he meant, and I can see what you are saying. Clearly with a centre to centre difference in pins, the wear would be greater, perhaps he meant that taking a pad out just exacerbates that and causes faster wear because the pitch is even further out on an increasingly worn track?

A similar discussion here


http://farmingforum.co.uk/forums/sho...-digger-tracks

I'm wondering if its because the sprocket only engages every second link, and/or if the sprocket teeth numbers are not equally divisible by the chain link numbers ?

[v8druid]

A similar discussion here


http://farmingforum.co.uk/forums/sho...-digger-tracks

I'm wondering if its because the sprocket only engages every second link, and/or if the sprocket teeth numbers are not equally divisible by the chain link numbers ?

As long as centre dimensions match Muz, the chain can be as long or short as you like ..... it's all about pin centres not track length .... if the track was just laid out on the floor, say a mile long, as long as the pin centres matched the sprocket engagement centres it'd just roll along the track .... it's why the system is called a track laying drive ...... just happens that they're endless on a machine ....... just a big rack and pinion drive ultimately.

[Locofitter]

Indeed, I dont want to take a link out as its not the proper way and will only add wear in other areas such as carrier assy. But I dont think theres much choice in the matter.
I've never purchased track or track chains before so dont quite know which ones to buy, are they categorised by machine type? Are there different types etc? How do I know what to get a quote for?

I have seem two of the same machines on ebay for around £8,500 each and have requested it goes through to the committee that we purchase one and break it down for parts.

The joys of obsolescence!