Undercarriage, New Technology

[John C.]

CMark, Thanks for the post

If you look at the D6T in the video you will notice it has the relieved tread on all the idlers. Problem I had with the relieved tread is that there isn't a generally accepted way to measure the wear on it. I haven't been with the Cat dealer in a couple of years now so haven't had direct access to past histories of how it has been working. The operator on the machine in the video said that machine hadn't had any undercarriage problems in the approximately 3,700 hours on the machine. They did have problems on a prior "R" model. I thought this machine was showing more wear than I would have expected for that amount of hours but I didn't measure it to make sure. This is a dump site and that machine pushes spoil from excavations in the greater Seattle area. Do you know if all the dozers got the relieved idlers?

 

[Cmark]

Measuring the relieved tread idlers is the same as standard center tread. There should be a machined area on one side of the idler which is used as a reference for the tread height. I don't know for sure if the relieved tread idlers are now standard system one fitment, but I suspect they may be.

 

[John C.]

They seem to be standard on the D6T. I don't know about the rest. I haven't seen any literature from Cat showing where a reference mark might be. The front idlers would be rough to find that mark unless it was cut all the way around the wheel.
What is your experience with System 1?

 

[Cmark]

My experience with S1 is limited. I got involved to a degree when it first came out and, as we know, had some problems leading to us converting some machines back to conventional U/C. However the majority of our customers at the moment are D8 and bigger. We have a couple of newish track loaders on our patch with S1 and I haven't heard any real complaints and they seem to be holding up OK as far as wear goes.

 

[John C.]

I guess it might be better to find out from anyone else who might be running the new stuff how it is doing. So if anyone has any experience with it or any more information, please feel free to post.

 

[Cmark]

They seem to be standard on the D6T. I don't know about the rest. I haven't seen any literature from Cat showing where a reference mark might be. The front idlers would be rough to find that mark unless it was cut all the way around the wheel.
What is your experience with System 1?

Here's the official word on measuring centre tread idlers. The diagram referenced is the one I posted earlier.

 

[earthscratcher]

talking with guys running the new stuff, they are very finicky on track adjustment and clean out, when they do fail prematurely, its been ran to tight , to loose, or not cleaned properly. they are fine for a guy running under warranty but when it runs out better have cat man on speed dial, you will have a hard time tearing into it without the special cat tooling.

it looks to me like they put all the wear on the pins and less on the rail,i run all rail assemblies to destruction no pin turns, a waste of money in my eyes.just wish they made the high track with a bigger front and back idler, rails wear out quick touching a small spot on small idlers.

 

[ih100]

Idlers, rollers and sprocket from a D6N i’ve Just been working on. S1. Tell me what you think.

 

[Nige]

I think it's f**ked ……..

Track & carrier rollers have taken a pounding. Idlers not so much unless they were replaced in between the last U/C overhaul and now.
Front & rear idlers pretty much the same wear %..?
Working conditions..?

 

[ih100]

I think that’s a fair assessment, Nige. 5500 hrs, original idlers front and rear, virtually original profile and virtually no wear on bearings, original sprocket segments not far from original profile, and the rollers speak for themselves. Wish I’d thought to take pictures of the box links and rails. They had some scolloping but Barely measurable with feelers and straight edge, but the wear on the rail edges was horrendous.

90% of its life has been on topsoil, 10% on sand. Quite a bit of batter work. 12 box links were shot, the others good enough to keep working. This is the trouble with S1, you can’t rework a box link, only replace. Can you imagine running new rails on those idlers, or worn rails to new rollers? Anything besides new chains with new rollers is a bodge.

 

[John C.]

I don't think I would have any trouble running another set of chains on that stuff. Did you get those roller measured. It would have been nice to see how far down the roller flanges were on the track pins. Measuring those front idlers is what I was talking about in an earlier post. You would be hard pressed to get some kind of calipers on there now, let alone with the chains and pads in the way.
The real problem though is that you aren't getting even wear rates across all the components. A percentage of wear on those rollers might give us a feel of how much money is getting thrown away when you install all new.

Thanks for the photos and the post!

 

[ih100]

I’d put new chains on the idlers and sprockets, but certainly not on the rollers. As you say, John, the wear is uneven, and at UKP £12000 per chain I wouldn’t take the risk. The biggest enemy of S1 IMHO is anything forcing the chains to twist, be it wide grousers or unevenly worn rollers.

I think on a D3 or 4 and the right application, such as spreading and minimal side-sloping a set of S1 would last 7 or 8000 hours. Trouble is those applications aren’t too common. I’d also be interested to know how they survive on a 953 over the long haul. Any takers?

 

[John C.]

I'm beginning to think that to get the most out of S1 over the long haul, you are going to have to store used until other used get to where it matches to get a decent runout. Do you think you can get away with just rollers and chains then? To compare your Pounds to Dollars, a pair of chains is over $28,000 with out the pad swap. I might be a little sore about only getting 4,000 hours on working easy material.

 

[ih100]

We could get away with rollers and chains on this one, and yes, if you had a few machines the same pitch and the puller to do the job, you could mix and match old chains. Finning reckon on 4 man-hours a link. Your prices come out a bit cheaper, but over there you have competition between dealers, we only have Finning Cat.