So what does a guy do when he gets 2 weeks off from work? More work! It was high time to change out the front left idler on one of my 977Hs... I got a new-to-me idler from Offroad Equipment and here's some pictures of swapping them out... I'll post more when I'm done... The new Idler The old one - slightly cracked... Machine without idler Swinging the new one into place And the new one in position ready to be shimmed and bolted on...
Ok question... Now that it's all in and bolted down it looks like the idler has quite a bit of toe-in... Is this normal?
Yair . . . spitzair. I am not familiar with your machine but idlers are usually aligned with and centred on the track-frame. There are wear-strips and shims to provide the adjustment . . . any toe-in would be an issue. One of the causes can be that the "Jaws" of the track frame are spread/bent just forward of the recoil assembly. Cheers.
Hmmmm.... Thanks Scrub, I'll do some measuring and see what I can find... The Idler and such is the same as a 17A D7 from what I've been told...
I have never seen a front idler wear through like that but then I have never seen one that out of alignment. I would say you either have a bent yoke frame or bent rod. if those are ok you then need to remove track tensioner covers and look at the guides that control the location of the piston pilot. Also take a real good look at the condition of the front idler wear plates. if those are super worn and not shimmed properly the put a huge amount of strain and wear on everything clear back to the spring pilot guides and even the spring itself cause nothing is inline to what it should be. Sometimes its not just one part but an accumulation of wear of many parts.
If I blow the picture up a bit it looks like you have some heavy wear on your guide strips between the orange lines. on your Idler bearing blocks there will also be wear plates that will be work as bad as these areas as they wear together. Just all part of the big picture.
Thanks workshoprat. I got it pretty straight with some shimming. There is definitely some wear on the areas your picture shows and we welded it up and ground it off and now it sits in there nice. Got the track back together too and calling it a day. Tomorrow I'll take it to my neighbour's for a few hours of work and we'll see how it does. Thanks for all the help!
Did you by any chance measure the distance between the "jaws" of the track frame at various points to see if they were all the same. The 2 legs should be parallel to one another. I can't see how a frame could spread in operation but the weird wear on the idler you removed was caused by something somewhere being out of whack.
Shimming of what and where? Please take some pics! I can see a bent track frame may casue this but if it was everything would be so tight there wouldnt be room for shims on the outer plates on the bearing blocks that keep it all centered in the track frame. Its more likely to be a bent yoke frame or rod. If you shim the bearing blocks to the yoke frame you are just bandaid fixing a much larger problem. Far as I know the only place shims are used on this machine is the end plates on the bearing blocks. I would need to see a Maint manual to be sure though.
There 2 sets of shims on the idler. The shims behind the horn plates are to adjust the side play, the others on the top are to adjust the height. If you want a copy of the measuring & adjustment procedure drop me a PM with your email address and the machine S/N. I assume it's a 53A.
Workshoprat, the shims I used are the ones under the side plates on the sides of the bearing blocks... Someone had shimmed it heavily to one side, now it's shimmed to the center... I didn't get any measurements Nige, but would certainly appreciate the procedure on shimming and measuring! I can't figure out how to send a PM from my phone, my serial number is 53A4922. This machine sees maybe 10 hours of use a year but I would like to have it set up right. The new-to-me idler did come with it's own bearing blocks that are nowhere near as worn out as the old ones. Another thing I noticed was the plate that sits in the springs in the bearing block was missing from one side - we made a new one out of some hardened steel that is the same thickness as the one that was left... Oh on edit I did put a straight edge on the track frames where I could and everything seemed nice and straight...
info Here some break down of parts if it helps https://mega.nz/#!Xo0y2SDL!HEH0o5CmJQkdm7JpWJs-4xB_7vv0rgWoDZAAbvBgBXg https://mega.nz/#!nxdUQaIZ!X0z6s89TEZm-z9MxArfqDX4tfnyRCRmKsjUa_ceWoZI
The shims are located inside the areas in red. Dimension X (both sides) should be in the range of .030-075", Dimension Y should be around .030".
That diagram looks to be for a newer series of machine than what he has. Thats closer to my 955L. In his pictires I can only see where there are shimpoints for the end plates. I dont see where you wouls shim it to set the bearing block to roller frame gap.
Thanks Nige, That diagram is similar to what I have except I don't have the shims for dimension X. I did have another good look at everything and nothing seems out of the ordinary except the recoil spring seems to be cocked to the side a little, and that in turn looks like it's pushing the tensioner arm over causing the toe-in on the idler... I'm going to have to take all that apart and fix it right, unfortunately I won't have time to do it this time around, I'll do that next time I come home on days off... Aside from a 203 hour job at my neighbours tomorrow maybe, the machine won't be doing much of anything while I'm gone anyways, maybe an hour or two here and there spreading some dirt... And that's just a big maybe at this point anyways. Thanks for all the help with this issue guys, I really appreciate it!
So can I assume you pulled the cover to the tension-er spring? If so clean it out real good and take a good picture of it. Sounds like from what you describe your spring pilot (pilot is the front part of the spring that holds the piston) guides are totally shot. Dont know if its the guides on track frame or on the pilot or even a combination of the two. On the diagram Nige posted albeit for a newer machine the X and Y tolerances are pretty critical from keeping everything in alignment and overworking and busting or wearing out the pilot guides which you are now discovering. Like I said before its all part of the bigger picture and all works together right down the line.
I didn't fully pull the cover, I just looked in the hole where the tensioner grease fitting is and the pilot is done. I'll try to get in there for a picture tomorrow...
hey spitzair if you grab www.teamviewer.com your welcome to login to my pc/ and use cat sis to research what you need. my email is [email protected] and yes it not miss spelt it cause heavyequipment was taken lol
Thanks for the offer Shawn, I do have a set of paper manuals and a parts book, is there anything else you can see using cat sis that I can't using my manuals? I ran the machine for almost 4 hours today and everything seemed to be working great, no noticeable problems and with the track good and tight things look straight to the naked eye... I will have to get in there and fix it right one day, I just don't have the time to do it now... Tomorrow I'm putting some new (to me) tracks on my other machine, I'll make sure to get a few pictures of that fun and put them up here...
Just an observation but that LH track is a bit on the tight side for my liking .......
Man thats a good looking old cat. I bet that 977 is a real brute of a machine.
Nige, I agree... The stuff I was working in was pretty sticky for some reason and it packed the rails full... Workshoprat, thanks for the compliment! I moved some huge boulders and uprooted some trees with it yesterday, it's a real powerhouse!
I bet it is! What engine does that have. My dad first machine was 955h. I have never got to run a 77 and i bet it a bunch of fun. Still bigger machine than my 955L.
It's got a D333 turbocharged engine. I did some engine repairs on the older machine a few winters ago, yesterday we started to change the tracks on that machine as the ones on there were finished and then some - I had them on the first machine and they came apart one day while I was loading trucks, and so I swapped them over... I found a good set of tracks and they're going on this machine now. I just need to wait for new master pins to show up...
And a few more...
Ok so I have a new minor issue. One of the new-to-me tracks is short a link, guy I bought them from cut one... I can get the links and bushing from Offroad Equipment for a great price so my plan is to get another master link set and bushing and run 2 master pins side by side in this track. Is there any reason I shouldn't do this? And Can I assemble the link and bushings with heat (lots) and a 20 ton shop press or will I need a full on track press to do this? I haven't checked to see if the track is streched enough to run with the missing link but I have my doubts as it looks like the pins and bushings were just turned in it...
Yair . . . spitzair. No problem to run two masters together and it is easy enough to assemble left and right link onto a master bush if they still make them the same as they used to . . . we used to bash them together with a fourteen pound hammer on the push beam. Some heat can help and make sure you have the links aligned. Cheers.
Yep, as a hint, don't try to do both links at once, push the bushing into one link til it comes flush, then do the other link, try to get it pretty flat across the bolt faces and use the track pad bolt holes to check your dimension. Most master bushings are made to just come flush with the outside face of the links as I recall.
Perfect, thanks guys! I'll order the pieces tomorrow and put it all together next time I go home!