I asked cat rep why the rails on my Dozier were cupping in the middle of the link, and I was told running too fast and too loose. I do run second gear ninety percent of time but do not run slack in tracks. Sealed and lubricated rails . Pins and bushing turned at 1800 hrs with new segments installed. Five hundred hrs since turn.thirty to forty percent left with front idlers with only 20 percent left. Rough ride too. Any ideas?
Do you have any idea what Part Number of links are on the tractor..? If you look on the side of the link right at the top just underneath where the shoe mounts there should be a number.
Tomorrow, I can get the part number. Cat sealed and lube installed late 2006.
What you are describing is normal for high hour operation on track links. Track adjustment and second gear operation has very little to do with cupping.
John, wondering if you know this by experience or what. I'm asking because we put a set of rails off of a D8N on our 7H after a re-bush. The tractor did a lot of long distance pushing stripping gravel pits and pushing trees. Probably more time than I'd like to admit reversing in 3rd gear. Couple that with a 7H not having a carrier roller, and we had our links wearing out like the OP states in around a 1000 hours. Maybe speed plays a bigger roll in reverse? In defense of the links, the chains were purchased used with leaking links and no idea of hours. They did measure at 60% height. They came off of a landfill tractor.
Links do tend to wear more in the middle as its the only part which touches as it goes around the idler.
Cmark, I was going to mention that, but I wanted to see what others had to say. I figured that out in about 5 mins of looking after I noticed the wear. Do carrier rollers help at all? Series 2 7H's have a carrier roller.
Carrier rollers help pin and bush wear if you're getting a lot of slap in the track. Whether they would help with link scalloping is, I think, probably doubtful. Depending on serial number, I seem to remember a carrier roller retrofit procedure for machines that had been shipped without them.
Ours was a 79Z..... I used to know it, it was one of the last ones before a Series 2. Dad still has it. If I could ever get my hands on it I would put the top roller on.
Cmark is right on. High drives have two idlers to wear the centers out of the rails. The cupping is more an issue of distance traveled rather than speed or direction. I always figured that undercarriage should have warranties based on mileage and not hours. The new electronic machines now have that.
This is an old post I made about a year ago. Nige asked for part number for track links onmy dDozier. Left side 106-1626 11. Right side 106-1625 11
Those Part Numbers are Heavy-Duty links. As others have mentioned the phenomenon of scalloping in the centre of the link is usually put down to the fact that it's the only point of contact with both the front and rear idlers as the link passes over them. I guess the $64k question is how many hours the links have operated since installation. Nobody else has mentioned it but an unbalanced machine can accelerate link scalloping wear. How well-balanced is yours..?
It may be a little tippy toe being it has semi u blade with tilt cylinder.
No counterweight or ripper I take it..?
Nothing on rear but drawbar.
Yair . . . Never worked around Hi-drives but, to me, for any given size tractor the idlers at both ends of the track frame look smaller than on an equivalent oval track machine . . . probably an optical illusion. I recall no such cupping issues on conventional tractors that lived in second or third gear forward and ran for thousands of miles. Cheers.
My sentiments exactly, Scrub. I have a competitor that has a 7H Series 2 that walks everywhere it goes, he doesn't own a truck and trailer. His machine has a carrier roller, back end MIGHT have 500 pound weighted drawbar, but he also has a semi-u blade whereas ours just had a straight cushion blade. The couple times I've seen the tractor I noticed no scalloping link wear.