D8R dozer undercarriage replacement

[Robert0769]

So you don't have an Operation & Maintenance manual.?

I bought a digital copy years ago while working on drivetrain as you suggested then haven't touched it since. I need to find how to access it again. I did ask cat a while ago and they said they'll get back to me then both cat and I forgot. I need to give the daily schedule a good looking. I check all other fluids, do a walk around and let it warm up. I'll aim to do better!

 

[Nige]

The “digital copy” should’ve been an Adobe pdf document that you could have downloaded to your computer and had it available as a permanent reference.

Contrast your approach with this guy and then compare the appearance of his machines with yours ..... “I got the operators manual out on the table with a cup of tea and box of biscuits and set about it in my spare time.”

https://www.heavyequipmentforums.com/threads/d8t-full-service-just-about.93125/

 

[ugis]

I noticed that the equalizer left side mounting was welded. This is probably why the left side of the track has not gone the right way.

 

[Bluox]

I noticed that the equalizer left side mounting was welded. This is probably why the left side of the track has not gone the right way.

Bingo I missed that but that is a major cause of a track mis alignment.
I'm gonna bet the pivot shaft and bushing is worn out.
Bob

 

[Nige]

Bingo I missed that but that is a major cause of a track mis alignment.
I'm gonna bet the pivot shaft and bushing is worn out.
Bob

I wouldn’t bet against the pivot shaft being so badly worn it can’t even be turned to get a 2nd life out of it even with new bushes. What’s the betting the oil tank is empty.? I was already assuming the equalizer bar was going to be toast. It wouldn’t surprise me to find the end bearings completely eaten away.

 

[nicky 68a]

My thoughts are that your front and rear bogeys carry single flange rollers.Your middle two bogeys carry double flange from memory.
Some D8N’s were offered without bogey’s and rollers were fitted directly to the track frame.
Your pivot shaft seals may not be leaking simply because the oil has run out along time ago.You can open the little drain plug on the track frames and watch the oil come up as it purges the air out.Then you go up to the battery box and fill the reservoir back up to level.I fear you may be waiting a long time for the oil to purge itself through unfortunately.
As for your eq bar ends,I can clearly see the seals still in place.They can be given two or three shots every few days.Don’t over grease them.Cat have struggled to get a definitive cure for lubrication and wear on these ends,and various modifications and upgrades can be found.
I think the D8R had grease points in the engine bay for the centre pin?

 

[nicky 68a]

That’s the plug that you want oil to purge through

 

[John C.]

It isn't hard to run up a bill on one of these. Now that your eyes are open a bit, you can ask the Cat rep all the questions posed here and maybe short circuit the usual phone calls once they have the machine in their possession giving you bad news about how much more it's going to cost. Make sure the rep includes miscellaneous hardware and environmental charges that get tacked on outside of any quotes that they do. It wasn't that long ago that $40K would have covered nearly every possible issue we have highlight for you. I'm thinking you are probably up around $60K now without messing with the bogeys and cushions. That would be exchanging the equalizer bar and any machine work that might be necessary for the pivot shafts and track frames.

 

[Nige]

It wasn't that long ago that $40K would have covered nearly every possible issue we have highlight for you. I'm thinking you are probably up around $60K now without messing with the bogeys and cushions. That would be exchanging the equalizer bar and any machine work that might be necessary for the pivot shafts and track frames.

With all that welding on the LH end of the existing equalizer bar I don't think it's going to qualify as a core for an exchange EQ bar. He is likely in for a brand-new bar.
If we're going to run a pool on it then my number is North of $70k if everything is done and done right. Band-aid fixes don't count.

 

[Robert0769]

I noticed that the equalizer left side mounting was welded. This is probably why the left side of the track has not gone the right way.

Thank you, I didn't get email notice of this response! Man they pulled one over on me lol!!

 

[Robert0769]

That’s the plug that you want oil to purge through

Thank you I'll try looking for this. Somewhere around the sprocket on the bottom?

 

[Robert0769]

With all that welding on the LH end of the existing equalizer bar I don't think it's going to qualify as a core for an exchange EQ bar. He is likely in for a brand-new bar.
If we're going to run a pool on it then my number is North of $70k if everything is done and done right. Band-aid fixes don't count.

Any chance you know how to grease the pivot shaft or is it only that oil? Nicky mentioned grease points might be in the engine bay? Thank you! So far looking at the shafts they're looking good and seals are in tact but I can't see the shaft under the seal. Could be a completely different story.

 

[Nige]

Nicky mentioned grease points might be in the engine bay?

The grease points Nicky mentioned are for the equalizer bar, not the pivot shaft.

So far looking at the shafts they're looking good and seals are intact but I can't see the shaft under the seal. Could be a completely different story.

Is there any oil in the pivot shaft tank.? See the attachment for location and how to check the oil level.

Thank you, I didn't get email notice of this response! Man they pulled one over on me lol!!

IMO they didn't. They offered a machine for sale, it was up to the buyer to inspect it and find all this stuff before parting with the cash.

 

[Robert0769]

The grease points Nicky mentioned are for the equalizer bar, not the pivot shaft.
Is there any oil in the pivot shaft tank.? See the attachment for location and how to check the oil level.
IMO they didn't. They offered a machine for sale, it was up to the buyer to inspect it and find all this stuff before parting with the cash.

Very true it was my responsibility to look it over which is why I'm not freaking out, but they did say it doesn't have everything it did. They said the repacked the front cylinders, changed all the oils, it has no super worn parts except the chain, had new idlers, rollers, sprocket.. so the rollers and sprockets looked good but for a blast to the past.. remember it turned out the gears in the left final drive were shattered, there was a napkin stuffed inside the warning light so I couldn't see it blinking, the sensor wires for all filters were cut and bypassed, none of the oils were changed, the front cylinders were not packed, they said it had a new scavenger pump but I had to replace that and found a 1.5" rock inside the pump. I even hired a heavy equipment mechanic to look it over before buying.

Now I know what to actually look at for the future.

 

[Robert0769]

The grease points Nicky mentioned are for the equalizer bar, not the pivot shaft.
Is there any oil in the pivot shaft tank.? See the attachment for location and how to check the oil level.
IMO they didn't. They offered a machine for sale, it was up to the buyer to inspect it and find all this stuff before parting with the cash.

Do you know where I grease the equalizer bar? I'll be crawling under in a bit and also checking that tank.

 

[Robert0769]

Well so far I've talked to 2 parts people and 1 service person at Cat.. I asked what kind of oil the pivot shaft takes.. none know and I'm waiting for a call back.. which I probably won't get. It's unfortunate I've asked Cat how to maintain the machine and please show me and they don't know. Yes I could read but when cat says just do this or that I should be able to believe them.

 

[Nige]

Do you know where I grease the equalizer bar? I'll be crawling under in a bit and also checking that tank.

E-Bar centre pin is not greaseable on your particular tractor.
End pins - see attachment. No idea which type you have but both types are shown.
Note that it's not grease you put in there but an 80W/90 gear oil. That is unless the seals have failed when it is acceptable to grease it until the seal is fixed.

 

[Robert0769]

E-Bar centre pin is not greaseable on your particular tractor.
End pins - see attachment. No idea which type you have but both types are shown.
Note that it's not grease you put in there but an 80W/90 gear oil. That is unless the seals have failed when it is acceptable to grease it until the seal is fixed.

I bet you could run the entire technical department at cat. You locate and research better than all of them. Maybe you can take the pay for 2-3 people and the dealer can save labor on the rest ha.

 

[John C.]

The kind of problems you are listing might only have been caught with Xray eyes. That's part of the problem with looking at old stuff. In many cases you just have to know that kind of stuff is going on inside by its age and type of use. You have to be a Sherlock Holmes by using base knowledge of what the machine was originally and what it is now. The odd wear pattern on the undercarriage would have lead to a closer inspection there. Slop in that equalizer bar would have been an easy find. A light out on the dash panel when the key was turned on might have made for a closer look there. Checking the pivot shaft reservoir was always a must on my inspections. Opening the engine panels and having a look around is a must. For a lot of years I didn't recommend oil samples. The new stuff pretty much requires it for the engines as crankcase vapors stay in the engines and dirty oils don't just flush out anymore with a oil change. The other thing to keep in mind about mechanics is that we are there to repair broken stuff. Most of us don't actively look for more work to add to the already overloaded schedule.

 

[epirbalex]

I am getting ready to go look now. I'll do my best to locate those parts. Any guidance on where they are would be greatly appreciated! Those are all new parts I haven't gotten to yet. I'm about 80% familiar with everything now. Yes it's the same dozer as the issues in the past! While I'm fixing the tracks I'll also be working on injectors.

Cat sos oil said engine has 40% diesel in it. I was told open the valve cover and turn the engine and watch the fuel lines for spray, otherwise it's probably injectors. That's where I'm at now. I'm hoping it's a line because if I don't see anything I'll need the next step.

Have an opinion on how to look for the fuel leak? Do I open the valve cover and look for leaks? If none, what the ?

Thank you!

I see this as a far bigger problem than worn out tracks . Is there any way the 40% figure could be wrong ? If its so and its be happening over several services the motor could well be damaged by now . Are you able to establish when the oil was last changed , if recently there has been a large oil leak or burn if the if the stick was not reading a long way overfull .