My track tightener spit its grease out of coil side, Is there any chance that the tightener can be taken out without breaking the tracks open? I am hoping I can just disconnect the idler push rod, pull idler as far forward as I can and have enough room?, or maybe enough room to put in the seals?, any pics or procedure would be MUCH appreciated. if the tracks need to be opened, does somebody have the procedure for that?, picture of the master link etc? can this be done in the field???
A quick look at Cat SIS and it looks like the track has to be split, front idler removed and the first roller off the track frame all need to come out. I have not worked on one of these so maybe someone who has can offer a alternative way to make this repair.
Got to split the tracks and take the idler/tensioner out before it can be disassembled unfortunately. Splitting tracks is a job for some really specialised hydraulic equipment (mobile 100T press) operated by a competent person because if the press slips off the pin someone can end up getting seriously hurt.
Wouldn't a D7E have the split master link that is held together with the same bolts that hold on the track pad?
Don't think so unless the OP shows us a photo of what the master link looks like. We have no Serial Number to go on so I'm blundering around in the dark a bit, however every prefix of D7 I looked at had a pressed-in master link pin. BTW I am assuming from the posted photo that the tractor in question is an "original" D7E, not one of these new-fangled electric drive jobbies.
Am I looking at the wrong s/n range D7E? in the picture it looks like a coil spring recoil style. The D7E I'm seeing in SIS has a nitrogen operated recoil cylinder. What is the full s/n of this machine?
I can tell by the pic that it's a D7E 47A or 48A. My 48A had a split master link since the rails had been replaced. Yes, I still have the service manual for it but Nige has pretty much summed it up. Takes about a big hour per side once you get the track split and yes it can be done in the field. Let me know if you need procedure or pics.
The 47A/48A machines aren't in SIS, only on microfiche or hard copy.
Yair . . . Assuming this is not SALT track . . . or even if it is . . . the master link bosses can be heated cherry red at the point where there is least metal and the pin belted out with a fourteen pound hammer and drift . . . in worst case scenario they can be split and rewelded to grip the pin. Cheers
it is definitely not the new D7Es, it is 1969 48a12279, thanks
I did a late model 17A without breaking the rail. If the tie rod through the recoil spring is in good shape and the threads and nut are good. Put a couple of pieces of pipe in the sprocket and collapes the recoil spring. Run the tie rod nut up and let the tension off the track. Unbolt the idler ram and the stops for the recoil spring. Pull the ideler forward to get slack. lift out the recoil spring assembly. Reseal the tightener piston and assemble in reverse. Will work it the tie rod and nut are good.
Track will not need split if you can get approximately 3'' gap when the adjuster and the pushrod are split. The u-seal that is leaking is on a bullet that can be removed through the gap. If the seal will still hold to push the idler forward than good if not you will need a porta power. As was said^^ you may need to collapse the spring also.
Hell Nigel us poor folks took out plenty of master pins with a sledge and a piece of bar stock with a pipe welded on for a handle. I used to sacrifice the master pin and cut a deep X in the ends with a torch to relieve the press fit, you have to cut all the way to the boss but not go past the pin. You can weld 2 gussets, one on the frame and the other on the idler guide plate and use a hydraulic jack on its side, ( pump down) to jack the idler forward. Easiest to break the track but you might get enough room if the tracks are worn. Once you get the cylinder separated from the shaft if you have enough room you can reach in and pry the slug out far enough to change the seal but not the fiber wear rings. No big deal but alligator links make it a lot easier.
Yeah, I have a tool made of a piece of tubing welded to a plate that can be clamped to a track pad to hold a drift in the right place to make it a one man job driving out a track pin. You better have plenty of gas for the torch and eat a huge bowl of Wheaties before you start by yourself , though. I have welded the end of the pin to the rail if it goes back in to easy, too.
update of job, I cant seem to get the idler ram loose, pulled with skid steer and tractor with 2 chains hooked to eyelet of idler...any ideas how to loosen the ram, seems to be jammed.
Yair . . . Not quite with you mudhole you blokes call things different. If you mean how do you move idler back and compress ram into cylinder the normal method is to use a baulk of timber (such as a railroad tie) cut to length and held it at a slight angle under a grouser immediately in front of the idler. As an off-sider drives the tractor forward the machine in effect is trying to "walk up" onto it . . . it goes without saying you have removed the grease fitting completely before trying. They normally shove back pretty easy but it might take a couple of attempts and be careful, that grease can be ejected with a lot of force. I have no knowledge of that tractor but in your picture it looks like the pushrod unbolts from the ram, a high pressure wash would make it clearer. Once you have the idler sliding freely you can tack-weld on couple of base plates onto the sides of the track frame and with a couple of twenty ton jacks or porta powers jack the idler forward with some bits and pieces welded to the slides . . . the action of pushing the idler back with the baulk should have bought all the slack track to the top and two twenty tonners will give you all the clearance you are ever going to get. You are mostly wasting your time trying to put any real weight on these sorts of components with tractors and such. Cheers.
thanks, I am now trying to pull the idler forward, so it is "normal" for the idler to need a lot of "persuasion" to go forward...not usually something wrong with idler and ram if it appears stuck?
Did you push the cylinder back all the way back by relieving the grease pressure first and driving on to block of wood like Scrub Puller described? Then, you have to separate the idler recoil rod from the cylinder (undo the 5 bolts at the flange right at the grease zerk and break it there). That way you can access the piston inside the cylinder when you slide the idler forward. Change that o-ring under the flat plate that's bolted onto the recoil spring housing. Hopefully, you have clearance to slide the cylinder out. If not, there's more steps involved.
Have you jacked the roller frame up to relieve the weight of the dozer from the front idler?
yes, I have the flange loose, pushed cylinder back... just not enough clearance because the idler is stuck and wont go forward
I have not jacked up the track...is there a way of doing this without heavy equipment in the field? I have tried to push the blade into the ground until I see the tracks pull up a little...I was thinking that the idler assembly slides on the rail independently of rollers etc, I have a lot of track slack at the front so I figured that it "should" slide...what am I missing in this ???
Yair . . . mudhole . They can stick but usually you can get a bit of "wriggle" with a crowbar and then push it forward with a couple of jacks as described . . . on some tractors the "yoke" can be unbolted or lifted from the idler once you get a bit of clearance. Heavy Metal makes a valid point . . . just a bit of weight down on the blade or a few digs with a shovel under the idler if you were running string. Cheers.
thanks everybody, got it almost back together, last thing is where the O ring seals the tightener flange to the push rod, there was a nylon ring that fell off when I took it off, it is tapered, I am guessing that the thin end goes towards the coil spring and the thicker part of the taper goes against the flat flange on the pushrod???
Goes like this \0]
perfect, thanks....I am back up and rolling!!!