Have cracked roller frame on our D6H ll. Have been adding oil for a while. Crack goes across top of roller frame just behind where the cover comes off for track adjuster. When we took bottom rollers off for replacement oil leaked out the bolt holes. The crack on the top of the frame does not go all the way down the side of the frame. Not sure what is inside. Is anyone familiar with a problem like this. I am just wondering if it is possible to repair the leak to prevent it from leaking oil out into the bottom of the roller frame. It must be cracked somehow on the inside.
thats very interesting as I think mine is doing something like that too accept mine cracked across the top of the tensioner housing ( I'll weld that up no problem) and then it is also leaking the oil out right under the pivot shaft and it makes it look like that roler has a bad seal but I don't think i'm that lucky. funny thing is that the pivot shaft housing isn't low on oil:beatsme Can't wait to hear what the experts say. this is the first time I have ever seen this.
To the OP. Let's see some photos .......!! I'm sure there will be a procedure for repairing it. Machine S/N would help too ......
D6H Series 2 & D6R REPAIR CRACKS in the REAR TRACK ROLLER FRAME / 3ZF D6H TRACK TYPE TRACTOR Special Instructions Media Numbers REHS0540-03 Publication Date 2002/06/01 Update Date 2002/06/17 {32pages** REHS05-40-02 May 2001 Available in SIS Repair & Welding of cracks in the rear TRF & dimensions for fabricating reinforcement plates Leaks typically out of roller mounting threaded holes, frame box section fills with oil slowly. 1st indication was during R&I rollers, next constant drip-leak. I fixed the leaks by cutting into the section from outside with TRF still on the machine & then fab'd 3/8" reinforcement plates outside & inside...memory my welder crapped out, borrowed auction special, it worked for 4" vertical up...so purchased new welder to finish the job! Machine had 12-14ft slope broad = hard on left side everything! Just happen to be reviewing this yesterday:tong
Leaking Roller Frame Cat D6H ll Nige I took a picture of the crack at the top of the roller frame and down the outside. Also took one of crack on inside. How do I attach the photos? StanRUS looks like he has a solution but I do not follow exactly how he did the welding. How is the oil getting from the main reservoir to the bottom part of the roller frame. Looks like there would have to be some welding on the inside. I was planning on taking the idler ends out of the tube so I can rebuild the track adjusters and clean it out good. Mine has been leaking for a while.
StanRUS the serial number on my machine is 3ZF5621. What are the Media Numbers you sent in your reply? SIS? I assume they are some kind of Cat publication. Where can one get a copy of them? Did you happen to take any pictures when you repaired your machine? Do you still have the machine? Could you take a picture of the outside? How does the oil get down to the bottom part of the roller frame where it leaks out around the bottom rollers? That is what mine is doing now. I put bolts in the bolt holes for the rock guards. Worked pretty well but it still leaks.
Leaking Roller Frame The Media #s are Cat SIS publication(s) Title = Special Instruction, Repair Cracks in the Rear Track Roller Frame #REHS05-40-02 May 2001 Update #REHS0540-03 SMCS Code 4151 3ZF D6H Available via SIS or from your local Cat Dealer (some dealers will give you the file print out some will not depends on their 'mood':Banghead) 1st contact your Dealer~Weld Shop foreman or Tech rep. From your photos you'll have to cut access windows to repair internal cracks @ bulkhead to roller frame, I would remove the TRF, easier to clean out the oil-grease residue & work on. Sorry can't posts photos D6H 3ZF5719 Std dozer went to Mexico, No repower engine available for diff steer pump Keep us informed
PWR - I have a copy of Special Instruction REHS0540. 70 pages so there will be plenty of bedtime reading. PM me with your email address if you would like me to send it to you.
Wow, it sounds like this could turn into quite the project and here I was thinking these cracks were mostly superficial. I have seen some of the D4 and D5 TSK's with a doubler plate that covered the whole side of the TRF. Could this be part of the "fix" or was it beefed up from the factory to stand up to logging ?
Nige, message sent. Thank you.
I think you are right turbo8781. No easy way to fix. The crack that is leaking into the lower part of the roller frame and out the bolt holes for bottom rollers is somewhere inside the roller frame. I see no sign of any place to repair from the outside. We have put some good welds on the external cracks but they crack back out. Almost makes you want to carry frame to Cat dealer, but cost would probably be more than tractor is worth. We are going to fix it ourselves as soon as we figure out procedure. Sounds like StanRUS had good luck on repair. I want to fix it to hold. Plan on keeping machine a while longer.
StanRUS when you repaired your D6H did you have to remove the recoil spring? I have never seen the inside of the D6H roller frame. I hope the spring will be farther back from the crack.
Most likely someone who didn't have access to the correct repair procedure fixing the visible cracks and then reinforcing the outside. It's not often the factory goes for doubler plates. The only way that a large percentage of structural cracks can be successfully repaired is by cutting windows in the strecture so that the welder can get inside and right to the root of the problem instead of trying to just butter over the outside with something that might look pretty initially but in the long term ain't worth jack schitt.......
Leaking Roller Frame Not my D6H, Owner-Operator's approx hrs @ repair 10thou. No I did not remove the Frt-Idler recoil tube assembly...cracks were located @ rear of pivot shaft & bulkhead; bulkhead is where your photos indicate your machine has issues. The recoil spring is located behind the front idler in the tube, then the grease adjuster assembly...You can remove the Idler-Recoil Tube assembly-STOP...DANGER YOU CANNOT work on that assembly without the correct tooling, FT plates, threaded rods, washers, 50T Cat cylinder and pump. 6H dose not have a oil drain plug, so you'll need a vacuum pump to suck out the oil or let the oil drain on the ground when you remove the Idler-Recoil Tube assembly. I vac'd out oil-grease, don't tell...refilled with 5gal gasoline & ran the machine around for approx 20min then ran the nose up on a slope, removed access cover and vac'd out the gas & residues. @ bulkhead I cut a access window in the frame side skirt with oxy-ac torch, reached inside & scarfed out existing welds...oxy-ac cooks the oil out of the cracks & surrounding area. Next using 0.035" Lincoln Outershield mig wire & long mig gun neck reached inside & rewelded the cracked area, power peening with needle scaler between each pass. Added reinforcement plate @ inside of RTF; 3/8" A514-T1 steel Repair was okay @ time of sale, just under 20thou hrs...operator retired...I rebored equalize bar cradle, left equal-bar RTF bracket & arranged cash sell to Mexican buyer...:notworthy Cat High Drives; RTFs crack, most new models incorporate improvements, thicker steel etc
Just wondering how the repair is going?
He's got get through 70 pages of instructions, LOL
Have been working on other projects. Looks like more rain is going to let us get back on maintenance. Still not sure how we determine where to cut the holes in the side of roller frame to do welding inside. Is there a cross wall behind the opening for applying grease to adjust tracks? Crack is behind this opening the has cover with four 3/8ths bolts. How big did you cut your holes? My problem is I have never seen the inside of the roller frame. Do not want to cut into a cross member inside of frame. When we get started, I will post some pictures. May need a little coaching. Can you reseal track adjuster without removing front tubes?
I think the first move should be to get the track roller frame off the machine, pull the front idler/recoil mechanism out of it, roll it over and remove all the track rollers, then steam clean. Once that's done you ought to be in a position to determine how to start repairing. With the oil chamber for the recoil system empty the construction of the assembly will be easier to determine, especially where the internal ribs are because you should be able to see traces of the welds.
Nige, I was hoping to do it without pulling the roller frame off of the machine. What is involved in pulling the idler/recoil mechanism out of frame? I thought that was a death trap that required special tools. I totally agree with you that is the right way. We have removed the bottom rollers.
Remove the two guides from either side of the track frame, six(?) bolts each, then pull the whole idler and frame and recoil assembly (known as the "cannon") out. The recoil spring is contained in the cannon. You can then remove the track adjuster assembly after removing a couple of brackets holding it in. Look up the end of the cannon and you will see the recoil spring behind a plate. If this plate is cracked or broken then you need to start treading cautiously. If all looks good and there are also no cracks to the outside of the cannon then you should be safe.
I'm sorry but IMHO that idea is not going to fly if you want the repair to last. The only real way to get at the bottom of the track frome is with it off the machine and turned over. Here is a generic illustration of the track frame. Your frame may not be exactly like it but the principle is the same. The full procedure is:- 1. Remove cover #3. Open the grease valve on the track tensioner and allow all the grease to run out and the tensioner to fully retract. 2. Remove oil & grease (or at least most of it) from the recoil compartment under cover #3. 3. Remove the master link bolts and split the track. 4. Look inside the track frame towards the front of the tractor and inspect for any signs of cracking in the plate at the rear end of the recoil mechanism. If there is none, proceed. 5. Remove 6 bolts from the inside and outside of the track frame and remove the cannon guides #2. 6. Carefully draw the cannon assembly forward out of the front of the frame, supporting it with a suitable lifting device or cribbing to prevent damage to seal #1. It will be rear-end heavy even if the front idelr is still attached. 7. Inspect the condition of seals #1 & #7, and wear ring #13. Replace as necessary during reassembly. 8. Remove the covers from the pivot shaft and remove/detach the equalizer bar end pin. 9. Slide the track frame sideways and off the machine. Disassembly of the recoil mechanism which is not required in your case is the process that requires the special tooling and great care.
Thanks Nige. Looks like for the long run there is only one right way to solve this problem. Will have to just gear up and get it done. I reviewed my service manual also. It will be a challenge because of weight of frame and lack of right machine to life and move roller frame. Working on plan.
Just read this post for the first time. Be very careful about vacuuming gasoline. A couple years ago there was a news report about a fellow killed while vacuuming spilled gas from his car floor. The vacuum blew up when the gas fumes hit the electric motor and the shrapnel killed a person whom was using the adjoining vacuum.
You just read the service manual! Did you read the special instructions? Access for repair is via removing the diagonal brace @ bulkhead (facing rear of tractor Nige's illustration #4) and cutting access windows in the side of the roller frame @ bulkhead. Using gasoline; vac'd with grounded air operated piston vac pump designed for transferring combustible liquids.