Minor issue here. Manual has a weird track tension adjustment where you pull the track up tight and then let it back 10mm or something. I am more used to measuring the sag in the top or bottom segment of track. So my question is, how much sag do you guys like to see in the top segment between the carry rollers? Also, the left track seems to loosen off in about an hour. I expected to find a pile of leaked grease at the adjuster valve, but didn't. There must be a grease leak but where? Thanks Ken
They want you to tighten the track up first to take out all of the slack which results in a more accurate adjustment. On the other hand just use common sense, not too tight...not too loose. Of course material that packs in the undercarriage will require some fine tuning. The left track on my 955 is doing the same thing. I can't see any grease leaking but I haven't taken the covers off yet. Maybe it's leaking on the bottom of the chrome rod or possibly a broken spring?
If it is not leaking at the grease fitting then it is prolly leaking at the rod seals. I have also seen them leak where the mounting flange is welded to the tube due to the weld cracking. As for the tension, 1.5" seems about right. Remember too loose is better than too tight.
Lee, to hijack the thread for a moment, are the rod seals at the big chrome crusty looking tube that comes out of the cylinder? I saw it getting longer when I applied grease but it's dry as a bone there. I haven't taken any of the covers off to investigate further yet as the track doesn't seem to get excessively loose.
On the D5, yes the chrome rod goes into a cylinder that has seals which seal against the rod. Some machines have a short rod, called a piston that pushes another rod that is connected to the idler. This is a D5G
Sorry Lee, I was referring to my 955L. I looked at my parts diagram and I couldn't quite understand where the grease was supposed to go and where it needed to be sealed. I don't have my book with me now but I thought the piston might have been on the spring side.
It sound like the tensioning rod seals. Check to make sure the rod isnt damaged and wearing on the seal...
I consulted the dealer and yeah, it must be the rod seals. In fact, the parts blow up on their computer is the same as the one above (thanks Lee) Can i safely disassemble this setup? I figure i can release the pressure with the grease valve, then break the track. What comes next? Does the idler come off the front rail easily? Ken
First check the o-ring (#26) it is under a plate that stops the grease fitting from being totally removed. If this is leaking you may not need to replace the shaft seals. To remove the idler, release the track tension, split the master link, it's best to split it on top of the idler. Remove the sheet metal on the side frame, some of the mount tabs will have broken off. Pull the idler off with the rod and yoke still attached. You can remove the 4 bolts (#28) so it is not as awkward and remove the idler then the rod and yoke. The idler will just slide off but if it is too tight or the frame is tweaked then you can remove the side plates (#6). You can then get to the end of the shaft and the seals. If you ever need to remove the recoil assy, Remove bolt #30 and washer then tighten the big nut, #24. This will compress the spring and remove the tension off the side frame so the retaining brackets #15-27-9 can be safely removed and then the assy can be lifted out. To disassemble the recoil assy, i suggest paying your Cat dealer to do it with their recoil bench.
Amen to that, have seen idiots almost kill someone using all-thread rods!
off topic but one machine i used to look after which was a D7HXR used to have a funny thing happen, the track would need adjusting so you'd pump up the track to the correct adjustment, run it ect and over the course of 5 or so hours of use the RHS track would get tight, to the point of having no slack in it at all and squeeling, then you'd have t let some grease out then it would be fine for 500 or so hours till it needed abit more grease in the track, all i could figure it was that it had a broken recoil spring which would work its way around and tighten the track up we learned to live with it and the quarry manager never gave us the ok to pull it apart to check my theory as it was a heavyly used machine
Thanks a boat load there Lee, that explains everything. Looking forward to giving it a whirl. Ken
Finally got at this job. Per the instructions above (thanks again) i popped the track off, pulled the shields off. Problem I was fully expecting to find a pile of grease somewhere under the shield. Over the last year we have pumped several tubes into it. But there is not a sign of old grease anywhere. The area is well protected and not packed with mud, so it can't have washed away. The tracks will loosen off in a day, so it comes out pretty quick. Its not coming out of the valve at the grease nipple. There is a release port with an Oring seal. Doesn't seem to be there either. I can't see into the area inside the spring. I wonder if its getting in there somehow. Before i replace those rod seals, i want to be sure that is where the leak is. Is there anywhere else it could be leaking that isn't obvious. Worse case i put the track back together, drive around the yard till it gets really obvious. Thanks for the info. Ken
Quick as a wink, i put the tracks back on, pumped them up, did a hundred counter-rotations, and repeat. Half a tube later, i finally see some grease accumulating inside the spring. Not sure why it would be getting in there, but at least i found my leak. Track tension piston rod seals seem ok. Any ideas why it would be inside the spring. Its must have something to do with the big draw-bolt inside to release the spring pressure. ken
I just finished replacing both sides on my old d5. The track adjuster(chrome section) has to seal both on the outside and the inside of the 'tube'....The piston has to seal on the inside and the seal on the front pilot has to seal on the outside. With mine, the surface was pitted and worn both on the inside and outside and so there was no way that the seals would work even if I replaced them. The track adjusters could have been re-furbished but it worked out cheaper to just by new parts. So it may not be just a case of new seals.
Can't make out the details of how the threaded rod fits into that housing but on the earlier piston type adjusters it's common to find the grease in the spring when the seals leak. There is no seal where the threaded rod passes through, just metal to metal that eventually wears to where it will allow the grease to pass.
I had one to crack here also. Did you check it? You gotta clean the grease off of it good to see it.
I pulled both track adjusters off and delivered them to the CAT dealer. After talking to the shop manager and trying to stimulate a little interest ( it was as if i was dropping off a DEERE track adjuster... he had that "what am i supposed to do with that?" look) a technician took some interest. They will disassemble and inspect. Try to figure out why the grease is leaking where it is. They confirmed there isn't any ports or grease passages in that area. i'm expecting a cracked weld. Picked up new grease lines for the blade. Mud removed the old ones. Also thought for the cost, i would replace all the bolts for the on the covers. I was impressed when i pulled those bolts out, none broke. Grade 10.9 metric bolts rusted in and seized. With some care and wd40 they all came out. NICE! Might as well put new ones in to make it easy the next time too. Not sure whether I should use locktite, neverseize, or both.
Examine to create sure the rod is not broken and dressed in on the close off...
Got the springs back this morning. They replaced the grease seals, and the grease release valve, so its all new now. The grease was getting inside the spring because the grease vent hole goes all the way through the bracket. The grease valve must have been leaking, and it went into the spring instead of out the front where you can see it. Anyway...I need bolt torque specs for the track pads, and the spring hold-down clamps. Anyone...? I have locktite on everything. Thanks, Ken
I'm no expert, and can only talk about my old girl....Old Magnet...how are you mate?....in the diagram it looks the wrong way around to me. the actual track adjuster in the diagram is the wrong way around. The tube faces backwards and the bolt just sits into it.....the face that has the grease nipples screwed into it is what the rod groups bolt on to. The long bolt butts up to the piston inside the tube. By pumping in the grease, the piston moves back against the bolt and the whole track adjuster/rod group and idler moves forward. The seals on/around the piston I guess could fail but in my case it was the chrome work on the inside of the track adjuster body that pitted and warped with age and so the seals of the piston couldn't seal. My solution was to replace everything for new.