Track bolts

[D6c10K]

Looking ahead to my winter projects, one of which is welding on grouser bar to my tracks to get them up to original height. I could do it on the machine, but that looks like a real pain. I'd rather remove the plates to make them easier to weld.

My problem is the bolts are really tight and some don't fit a socket real well because of wear. One plate is missing a bolt and the other three are loose, but it's still pretty tough getting the bolt to turn out of the nut. Are the nuts made with an interference fit?

Is there an easy way to get the bolts loose? Heat the nuts? I'm tempted to torch the heads off and buy new hardware, but a set Cat Classic bolts/nuts runs $473

Any good source out there for track bolts? (3/4-16 x 2 5/32 long)

 

[Cat Wrench]

Do it on the machine. Put the machine on stands and use a jack to turn the rails. Years ago (20+years) I did two D8's back to back and this worked well.
As for your loose pads, cut the bolts off with a torch.

 

[SE-Ia Cowman]

I cant tell you a lot about track bolts but I have allways wonderd how the heck they can be torqued to such a high torque. If you look at a torque chart for grade 8 3/4'' bolts fine thread it is 320-420 depending on wether you use oil or not. I have hammered on them with a 3/4'' impact and beat them with a hammer and hammered them some more and still had them come loose and I know I was way over 420 ft/lbs. I would like to know how tite they get them when they put them on a hydraulic impact table at the uc shop. Have you priced new shoes? Does the labor and cost of welding grouser bars on and removeing all the shoes and probably replaceing all the hardware still give signifacant saveings? We put a new set of shoes on the
7R this summer and Zigler beat Berco By $2000 and that inclued putting them on. We also got to keep the 24'' extream service pads that they took off and they fectched $700 at the scrap yard.

 

[JDOFMEMI]

Just do them on the track. Held the one side at the front at the idler, and the other side at the back on the sprocket. This way you are welding flat instead of sideways. Big rod or big wire feeder makes it go faster.

Last one I did was a D-9L, 2 welders and a helper finished in 2 days. Helper sat in the seat to rotate the tracks after each weld. 2 rotations, one to tack them on, second to fill it up.

Buying new bolts takes away a lot of the savings compared to new pads.

The bolts get bound on tighter due to the dirt, rusted threads, and bending from rocks, etc. When I have replaced pads, usually have to cut at least half of them, and that is with a -ss kicking I-R 1" impact with 170psi air feeding it.

To do it yourself, like stated above, use a jack to rotate the tracks, and just work at one position, front or rear, till all the way around, then switch.

 

[Komatsu 150]

I cant tell you a lot about track bolts but I have allways wonderd how the heck they can be torqued to such a high torque. If you look at a torque chart for grade 8 3/4'' bolts fine thread it is 320-420 depending on wether you use oil or not. I have hammered on them with a 3/4'' impact and beat them with a hammer and hammered them some more and still had them come loose and I know I was way over 420 ft/lbs. I would like to know how tite they get them when they put them on a hydraulic impact table at the uc shop. Have you priced new shoes? Does the labor and cost of welding grouser bars on and removeing all the shoes and probably replaceing all the hardware still give signifacant saveings? We put a new set of shoes on the
7R this summer and Zigler beat Berco By $2000 and that inclued putting them on. We also got to keep the 24'' extream service pads that they took off and they fectched $700 at the scrap yard.

I don't have a book in front of me but I believe the torque spec for track bolts is considerably higher than the spec for a standard grade 8. We never had an impact big enough so the last few times we did track work we just used a torque wrench to finish. As long as the pad isn't worn from running loose they stay tight if the bolts are of good quality. We had a lot of problems with early aftermarket bolts.

 

[QuickTrax]

My book says 750 +/- 35. This comes from the Itm torque specs.

 

[RobVG]

I don't know if you need it or not D6c10K, but here is some good info on welding those grouser bars-

http://www.titussteel.com/grouserbars_weldprocedure.htm

 

[John C.]

Track pad bolts are turned until the bolt actually starts to stretch to the point that it will not return to its original dimensions. It will be a little longer and a little thinner. All use the torque turn method so they are really tight. As I recall a D8H or K was torqued to 250 foot pounds and then another two flats. Each size of bolt has a different initial torque specification but all that I've worked with held to the extra two flats of turn.

Basically the bolts are ruined when they are installed so that's why I never reused them. You can reuse sometimes if you have to but generally they will be hard to start in the nut the second time. They are real easy to cross thread.

As far as the grouser steel I have used big square rebar and once used formed grouser steel but by the time you get through with the process you got more money than a new pad is worth. You can probably make it work if you have a fire hose of a squirt gun welder.

Good Luck!

 

[D6c10K]

I'm probably better off doing it on the machine to reduce cost. Seems like I asked the local track shop last year and aftermarket bolts would run around $300. Even that's plenty.

If I were using the Cat to make a living I'd just buy new pads, but since it's a farm dozer I'm willing to put some of my own time in to save money.

The advantage of using new bolts was I could do the welding without filling up the shop with the whole machine. That's the only place I have with heat and concrete floor.

I may make some stands by welding some old bottom roller shells together end-to-end. To fit it in the shop I have to drop the blade, but that's not difficult and will give better access to the tracks anyway.

RobVG, Good welding info...I figure I might begin to get decent welds by the time I'm half done.

 

[JDOFMEMI]

JohnC is spot on about the torque-turn method. You can cheat and use a BIG impact, but I have seen many of them come loose with that method.
A D-6 is much more forgiving than a D-8 or D-9, but still will cause problems if it is not tight enough.

When the dealer does the big ones, they use a hydraulic torque wrench. Initial torque is 450 ft-lb, if I recall, on a D-9. When it is already 450, then you go another 120*, it is TIIIIGHT. If you don't, and you work in any rock at all, they will come loose and ruin the bolts, pads, and in extreme cases, the rails by deforming the holes till they will never stay tight.

D6c10K

Sounds like a good winter project. All the welding will keep the shop warm and save on fuel.

 

[PAcattech]

D6c10K - D6C 3/4 track pad bolts torque to 220 ftlbs then turn 120 (2 flats )master pad bolts turn 180 (3 flats) put oil on threads Like others have said if you dont torque turn them they will come loose

 

[D6c10K]

Man those are tight...especially the master link bolts. 220 ft/lb + 180° turn would be about more than I can pull.

JDOFMEMI...If you're looking for that "Deg" sysmbol on your keyboard, hold the Alt key and then type "248" on the number key pad and you get ° Just some useless info cluttering up my brain....

 

[JDOFMEMI]

Lets see if that works. 90:Banghead:Banghead

Not working on my keyboard. Thanks for the tip though. I guess I will still have to use 90* as a crutch

 

[Cat Wrench]

Lets see if that works. 90:Banghead:Banghead

Not working on my keyboard. Thanks for the tip though. I guess I will still have to use 90* as a crutch

I push alt key and then the number 0 and get º. I use a Mac so it may be different.

As for the track bolts, I usually use a 1/2 to run them down snug and then turn them with my industrial 1 inch gun a couple of flats.

I doubt very many readers on here understand just how different a automotive 1 inch impact and an industrial 1 inch impact really are.
A good industrial 1 inch gun runs about $2200-2400 new in either IR or CP.
A 3/4 or 1 inch air line supplying it is night and day different from a 1/2 hose.

 

[JDOFMEMI]

I'll try it again. 90:Banghead:Banghead

Back to banging my head. That didn't work either.

I hear you about the impact guns though. And dont forget the ones that confuse Central Pneumatic (cheap import) with Chicago Pneumatic,(quality US made)

My service trucks usually run with the air turned up to about 170psi, and big hose to get the most out of a gun. Usually the 3/4 IR is enough for most jobs.

 

[Billy X]

Be a little careful if you have sealed chains and are thinking about welding the bar on the machine, the plate gets very very hot and I would keep an eye on your pin temp while in the process. I have heard of quite a few horror stories about dry pins soon after the job. For this reason we chose to remove the plates and weld on a bench and replace with new bolts. All up we saved about 4k on new plates for a D8 size tractor. The small price for new bolts is all worth it if you have sealed chains with alot of life left in them as we all know the cost of having dry links resealed or worse replaced.

 

[D6c10K]

JDOFMEMI,
You have to use the number key pad at the right end of the keyboard to get the ° symbol...hold down the ALT key, type 248 and then release the alt key.

Found the "cents" symbol I've been looking for ... ¢ (alt 155)

Billy X,
Hadn't thought about overheating the track seals...have to consider that. I'd hate to screw up the chains.

 

[Mccahilldozing]

I have a 1 inch impact gun that I got from Harbor Frieght that I use for tightenting track bolts. It works really good for a light use gun. I put it up against a CP impact gun when I was installing a ripper on a D8k and it actually had a little more torque than the CP. I think the gun cost me about 300 bucks. Make sure you take off all the paint on the area where the bolts tighten down to though. We put some pads on a D10n and didn't take the paint off. Well about 50 hours later the pads were starting to come loose. There is a guy out here in California that does track service for us. He has a track press set up on the back of a Semi trailer. He comes to your yard and can do all of the things that a big shop can do. Its pretty slick.

 

[D6c10K]

Decided to go ahead and buy a set of track bolts...got 280 bolts and nuts for $299 including tax. (3/4" bolts) They're Korean mfg...we'll see how they work. Track shop says they use them all the time without problems.
No rock around here to speak of...mostly black dirt or clay so they shouldn't see much abuse.

Called Cat just to check price
Original Cat bolts: $820
Cat Classic bolts: $473

I'm going to need a hot saw to cut the grouser bar to length. Cut one on the bandsaw to see how tough it is. Would work ok if I put a new blade on after each cut....pretty tough stuff.

Now I just have to get ambitious about starting the project.

 

[Greg]

guess we have to use d-e-g-r-e-e if the alt0 won't work.

Now to the subject at hand. I tried reusing track bolts one time when putting new rail on. Had to heat most of them to get them off. Wound replacing the whole bloody bunch after they worked loose. Just like I got to put pads on the new rail twice.