Right track outer 2 bolts are sheared off, inner 2 bolts still holding track together. Now, can these bolts be drilled and extracted out so we don't have to separate track or would it be best to get a new link and beat out fouled link to replace it?
Use a strap or come-a-long to hold the track together and get the track pad off. Get a welder to weld a flat bar with a hole over the broken bolt (or a nut)and the bolts will likely come out pretty easy and save you having to change the link. It would sure beat trying to drive a pin out and a new one in to replace the link.
Yes that was option but my welder guy just went on a bear hunt & will be gone for 10 days. I can weld but not a pro at it. But, I like your idea, I was going to try to weld another smaller bolt onto the broken one, given they are snapped flush with the link, it feels like they are.
Put a flat washer over the bolt first so you don't accidently weld the broken bolt to the link. I'd still take the pad right off because the bolt will be sticking up where a larger nut would fit right over it and make for a better and easier weld. Having the bolt sticking up is a big advantage.
I'd get the master link where I could easily work on it, slack off the track adjuster and after taking up the strain with a come-along (carefully) remove the master shoe. The put back the unbroken bolts with a load of washers so the master link stays together and have at the broken bolts as suggested above. The other option is (despite your reluctance) to get the master link over the rear idler and split the track completely. This would give you unrestricted access to the threaded part in the bottom half of the link and make welding a washer/nut on to the broken piece of the master link bolts easier.
It's really not that big of a job to slack the track and split it just over the rear idler. D4H would be a walk in the park over the last D9L I did for a broken bolt. And that was easy. A big block under a grouser and back the machine up to put the slack behind the sprocket... done deal. Just be sure to check the alligator jaws for excess wear.
You know having worked on D10s for the past few years I was thinking the same thing when I saw it was a high-drive D4 ...........
just went through the same issue with my d3. ended up getting some "extractalloy" rods and building up the weld on top of the broken bolts, build up high enough to weld washer and nut on top of broken bolt bolt. Allow to cool completely and they should back right out!. Took me about 2 hours and $50 bucks worth of rods vs the alternative, new links, track press, etc.......
Once you've done that melt some candle wax down the side of the bolt while it's still hot. The wax will work its way into the threads and make the bolt come out much easier once it's cooled completely.
Yair . . . Okay, I have to ask . . .why do the bolts break? Cheers.
Yep, Hi Nige..This is the same machine we had the major transmission failure in, got that all worked out . now she is running too good and here we go again with more issues. As all who are following this thread, the entire under carriage is new, why those bolts snapped I would assume whoever did the work on this machine before I got the pleasure of taking over is they came loose (here's your answer Scrub Puller?) probably from not properly torquing them down. I came across other failures on this tank from incorrect torque, wrong parts, missing parts, parts installed backwards, etc!! I think I will post later what I had actually found while tearing apart, wow, will be like reading "times best seller"!...really. have to grab a fresh beer and chips...anyway, OK, I have SIS access (yea! Nige!) And got service manual (amen,finally) so yes I see De-tensioning the track & blocking up grouser at the rear sprocket and pulling shoe would be in order. Remember, I do not own this machine, just help to keep it running but know there are ways to safely cut corners..Problem is the owner has the keys and this guy is out on hunting trip so either wait till he gets back or... Can I do it from the EXACT opposite from rear sprocket (the link is parked midway over the front idler)? If so, how to work with the tension on the track in this position? Will it slacken? Don't want to get myself in a pickle. Although she is sitting on firm level ground I'm still leaning towards waiting for ign. key to back up track to "service position"
You mean to say you can't find a replacement Cat key.? They go for about 50c each on eBay.....
This is why I ask you guys first!
LOL, I buy them by the bag of a hundred, seriously! You can do it over the idler, I would think a couple jacks on a timber under a grouser at a safe angle might give you enough slack, make sure to get the come along on and tensioned securely before trying to get the split links apart. Scrub, I usually found that if the bolts failed early on it was because the threads weren't lubricated before tightening/they weren't properly tightened/they were not rechecked after a shift or two, or something in the links or track shoe was not cleaned well enough. The master bolts are long and will stretch more than the other bolts, and the links will sometimes take a bit to settle in also. If they've got lots of hours and fail it's usually just metal fatigue sometimes caused by using too wide a track shoe for the conditions. Running a swamp pad dozer on hard ground will break the masters in a shift, I've seen it. YMMV
Ok got a key, got track blocked up and attempted to remove final two bolts. Let penetrating oil sit overnight. #3 came right out, last one moved 1/4 turn and frigging murphy's law snapped clean. S.O.B. Removed shoe & flopped back track to reveal... So now we got 2 bolts snapped about 1/2" in each link and one snapped flush. The bolt that came out was RUSTED bad, so this appears to be the root cause, the bolts were never lubed when they were installed. Oh crap, no way to weld inside the 2 they are too deep, gonna have to try to drill and extract. I would love to pull both links & get them in a drill press or just replace 'em but how to get them out without a press, probably trying to beat the pin out would just destroy everything or if it's even possible.:Banghead
There are a few questions to consider here. How old are the tracks, is there still lubrication in the pins and bushes? Where is the nearest place with a track press? If the tracks are in good condition and there is a company with a track press nearby, with a small machine such as a D4, I would load the track onto a pickup and take it to have a new half link fitted. If the lube has already gone, I would use the heat/BFH technique and install a new half link myself. If the tracks are in good condition and there is no track press nearby, I would probably put some more time into trying to get the bolts out.
See if you can get some of this rod locally, or order it in, seen it work, worth a try: http://www.airgas.com/p/ESA69201007 https://weldingsupply.com/cgi-bin/einstein.pl?PNUM:products:1:UNDEF:AND:69201007 off the ESAB web site: Stud Plus: A specially formulated AC/DC reverse electrode designed to be a cost effective way of removing broken studs, bolts, and taps from holes. Work on all grades of steel fasteners - stainless steel, grades 2, 5, 8 and case hardened steel bolts. "Kit" package contains 8 sticks 3/32" diameter, 5 sticks 1/8" and 4 sticks 5/32". Also available in Handi-Pack Display unit. Tensile strength: 120 ksi to 180 ksi Current temperature: AC/DC Diameter (in.) Length (in.) Wgt(#) and Container Stock No. 3/32, 1/8, 5/32 1# Tube Kit 69001015 3/32 14 1# Tube 69201006 1/8 14 1# Tube 69201007 5/32 14 1# Tube 69201005 3/32 9 5# Tube 69200006 1/8 14 5# Tube 69200007 5/32 14 5# Tube 69200005
Yair . . . Catmandude. Can you borrow or hire a magnetic base drill . . . you may have to weld up a jig/plate to mount it to. If you need to get it mobile I would just weld the alligator teeth and the plate to the rail, nothing much to lose. Cheers.
Always good to hear a success story.....