Here is the thread of another old machine, a Case backhoe 680G from year 1979 located in Australia. As it has been sitting for a while and therefore missing quite a bit, the intention is to bring it back to reasonably functional level to help out to build a new residence on the lifestyle block. Without knowing much of the history of the backhoe i can only speculate it is an ex government fleet and in some point of time sold to private hands whereas only the bare minimum has been done afterwards. Since i do not have a great deal of experience with that kind of equipment i have probably some stupid questions to ask and perhaps not so stupid one as well, hopefully everyone is fine with that.
Comparing the dashboard images from the service manual and what this machine has, can anyone comment are those VDO gauges part of OEM product line made for Australian market or more likely aftermarket modification by someone else. Thinking of replacing all of those along the way when sorting out rest of the electrical things.
Looks like someone has fitted them later. I did the same to my 580K after trying to track down a working dash (for a realistic price)
I kind of leaning towards the same conclusion that things are not factory fitted, hence it looks too well and neatly done to be an aftermarket build lol.
Otherwise slow and steady progress fixing things up, both boom cylinders got repacked and some new hoses to there as well, few more cylinders to go, steering and front bucket ones are next in line. Also I noticed there is no engine oil refill cap, only a drain plug and large oil check dipstick, is that being used for the refill as well?
In regards to the engine oil fill -- Yes oil is added through the dipstick tube. You have a 336 cubic inch engine in it.
Now was the time for the alternator to seize itself and snap one of the drive belts as well which were in the state of deterioration anyway. Trying to prepare things for the belt change though not sure how exactly to go from here. Apparently the big thing is to get the new belts around the crank pulley. Could someone comment from their experience what would the easiest way to do this. I am thinking of pulling the radiator and oil cooler out for easier access as i need to change fluids anyway, hence not sure how much work is it to do that, looks like a very tight fit in there though at least manual does not say that body panel frame needs to be removed and it should come off from the front. About getting the belt around the crank i am wondering is there a coupler between the hydraulic pump to slide it back and slip the belt in as i seen on 580 series or does the pump needs to pulled out completely on that machine, thanks. Also i take it has B type main v-belt and A type secondary one.
The best way to change the belt is just like you are thinking. Drain the hydraulic oil tank first. There should be a steel hyd. line with tee in it midway on the left side of the frame next to the engine with a drain plug. Loosen the fill cap to remove tank pressure then screw it back in a couple of turns to prevent a huge gush of oil from coming out drain. Then remove the oil cooler, next drain the radiator. Raise the loader all the way and put the saftey locks on both hoist cylinders. loosen all the pipes and hoses on the hydraulic pump. Next remove the two big bolts that hold the pump on the front motor mount assembly so you can slide the hydraulic pump forward. Be sure to check the pump input shaft for any wobble that may be caused by a defective input shaft bearing. Most important next is check the splines on the shaft for excessive wear. The hub on the crankshaft damper will have an equal amount of wear. The belts are a matched pair. I would recommend OEM belts from a CNH dealer.
Once again thank you for the advice Tinkerer, i think the direction is in there now and lets see how does it work out, will keep things posted.
If there's any seepage on the crankshaft front oil seal, now's the time to do it while you're close...
Ordered new OEM belts and genuine Bosch alternator, not much chance that belts will arrive before the beginning of the new year. I take trying to remove the hydraulic pump coupler is the first attempt to make a gap for the belt and if this does not work then the pump itself has to be pulled forward, by the looks of it similar scenario like 580 series belt change, double amount of coupler bolts though.
Right, finally got all the belts changed, the way I did was not probably the most professional but looks like it works. I decided not to touch the shroud or the radiator, it definitely slowed things down but there was still enough room to get the pump coupler bolts loose and slip new belts in. To get the pump off from the frame I bought some builders plates and threaded rods from the hardware shop, though coupler itself was really stuck to the pump and I decided not stress about it and left it untouched, not sure is it a good or bad thing.
Also with this round of repairs all front loader hoses and some tubes got replaced, new alternator and pulley, new air cleaner and intake hood. Next thing is to do the electricals, gauges and rewiring of the ignition. Need to change transmission fluids in gearbox, shuttle and in transaxles, then it should be all fully serviced for time being. All comments about the wiring scheme welcome.
Looking good, squad. Where did find the new air cleaner assembly ?
I got the filter housing through the australian ebay and the intake hood from the local retailer, somewhat impressed that those parts are still available, though heavily overpriced imho. It is an assembly made by Donaldson and excact match to replace the old one, part nubmer G080061, type FWG.
Sometimes we have to pay tooo much to get an otherwise unavailable part. Case wanted $162.00 US for a tapered bolt that locks an axle kingpin. That is just stupid. I did not buy it. I salvaged the old one that took out of it.
Almost there to finish off the dashboard and wiring under the hood. Bought a small enclosure box to cover the solenoids and the main fuse, backed it up with 4mm aluminium plate. Not so much intentionally i managed to get alternator with tachometer pulse output which should work well with the VDO unit and i can scrap the mechanical one.
Nice work !!!
Managed to finish off all the wiring and the dash which is almost complete, left some provisional options to have a pilot lights and switches if there is a need to add something in the future. All gauges are functional except fuel one as i hoped the existing sender to work but it does not and has to be replaced. Oil pressure reading is something i do not know what to think of as it shows one constant reading around 50psi and does not react to rpm changes or when engine warms up. I replaced the old VDO sender with new one which was hooked up to the hose from engine block to air compressor with T-fitting, shown as No 10 on the diagram, if anyone could comment that it would be great.
Your engine oil pressure sender is #25. That is where you should source any oil pressure gauge / indicator. I would prefer a mechanical gauge.
Yes i did check this diagram as well, though i can not see where the sender is attaching itself to, there are only two outlets for the compressor hoses on this side of the engine block or am i missing something? The foto is taken where the old and new senders are atm?
That is the correct way that Case connected the oil pressure sender and the compressor supply that is shown in your photo. But, that surely isn't your new sender on it there is it ?? Also it is hard to see, but it appears the tab for the gauge wire is pinched.
This is a photo of the old sender which i have replaced for now as i did not have up to date photos from there. As i know by default this model does not have pressure gauge and had only the dummy light therefore my guess is either the supply to sender is designed to be somewhat constant, the new sender is faulty or then the engine has blocked oil passages, any other suggestions?
The sending unit may not be the right one of it is defective. Get a clean grease gun hose and a air pressure gauge. Remove the sending unit from the block and screw the grease gun hose and air pressure gauge in its place. See what you have with that set up.
Thank you for the advice Tinkerer, that is a creative approach for sure lol hence effective and simple, will keep the results posted.
hooked up the air pressure gauge as suggested and got the same reading, minimum of 50psi at idle and up to 60psi at higher rpm. Not sure what to think of that, engine starts and runs well thinking of leaving as it is and see how does it behaves. also i am using 40 weight oil instead of 30 as i got some of that in stock but surely that should not make any difference or should it?
Sounds good to me. All engines have an oil pressure regulating valve that prevents damage on cold starts. Your oil system is in good enough shape that the valve is always regulating the pressure, not the pump output vs bearing clearances.
lifted off the rops canopy to sandblast it and to give it a new coat of paint at some point of time. Also i am preparing things for the small brake line overhaul and wondering is there any reason to stick to OEM brands such as bendix and midland or are generic manufacturers fine to use as well, i mean like valves, brake chambers and etc? have to say brake components are looking reasonably priced compared to some other backhoe parts as most of those are common truck parts and easily interchangeable. here are some photos about the rest of the progress.
good to hear that and thank you for the reassurance Delmer
Time for another progress update, probably the most noticeable change is that the backhoe has brakes after a decent overhaul of the airline system, managed to replace most of the valves and hoses. Apart from just installing the new parts i decided to add anti-compounding to the system as well and it worked out great, two extra hoses and one additional double check valve to the system. Also scrapped clutch cut-out feature and some switches which did not had much purpose now or before. I used the Tinkerers idea to add nitto air-fitting into the line and it works great, useful feature it is. Also steering cylinders got repacked along with added new hoses from the cylinders to the steering rack. In addition finished off the backhoe control tower and dashboard with minor detailing and elements. The battery switch will be also added to the plus side, i take continuous 300A and max 900A current rating should be fine for that system, bought the Blue Sea System m-series 6006 on-off switch for that, their product quality is excellent imho. Next things in the list are to patch-up, sandblast and paint some of the remaining body parts, get new set of tyres and to overlook the boom/dipper/bucket hoses and pipes as the previous work has not been done as it should had.
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For the record here is the parts list i managed to cross reference with the originals, hopefully it is useful if someone would do the same type of overhaul, though some parts are hard to find. d-2 governor no: 275508N bendix ref: 275491 e-3 treadle pedal no: 283927 bendix ref: 101482 pacific e-3 foot valve no: 277863 bendix air chamber: 24/30 st-4 safety valve 150psi no: 284142 bendix qr-1c quick release valve no: 289714 bendix ref: ABC289714 pacific dc-4 double check valve no: 278614 bendix ref: ABC278614 pacific sc-3 one way valve no: 800372 bendix ref: ABC5003980 pacific pp-1 air brake valve no: 101439 bendix lp-3 parking brake pressure light switch no: BE13240 haldex pr-2 pressure protection valve no: 277147 bendix r-374 pressure reducer valve no: R374-02AP parker watts cd-1 drain valve no: 103385 ref: ABF123 pacific
Looking good, Squad ! Nice high quality work. Keep those photos coming !!! I drilled a hole in the side of my cab so I could get access to the pins at the bottom of the foot pedals. Removing the pedals makes it 10 times easier to get at the mounting bolts in front of the pedal.
Thanks Tinkerer, will try to keep the photos coming as it goes and yes i know what do you mean about the foot pedals, as the mounting bolts can not be removed without removing the pins and pins will not come out unless pedals are unmounted lol
Started to change gear oils today and encountered a situation where gearbox was full of water, i mean completely full, from top to bottom, without much of oil in it at all. When I opened the fill plug there was like 3L before it dropped to the fill level and another 3L to the bottom plug from there. I take the rain has got into the gearbox over time and pushed the oil out from the top breather valve though could there be another explanation for that, it would be great if anyone can share their thoughts. Also I am wondering is it fine to put fresh oil in right away or should i look the way how to get rid of the remaining drops of water in the gearbox. Oil in central differential and planetaries was fine, shuttle had a red ATF which looked very old and dirty but not too much mixed with water. I got a 20L bucket of THC fluid from the local dealer, should be enough to let some of it drain through and then to do the final refill.
The boot on the gear shift lever is the only way for water to enter. Pull the drain plug and let it sit for a few days if you can let it sit that long. Fill the box with diesel fuel. Raise the rear wheels off the ground and put it in 3rd gear and run it a couple of minutes. Then drain it. let it drain completely again, then fill it with 80-90 gear oil. Hopefully there is access to a drain plug on the torque convertor. Otherwise you will only be able to drain part of the shuttle oil.
Thanks for that, cleaning up the gearbox in that way sounds like a plan and yeah I am aware it is not easy to flush the torque converter, thinking of doing more frequent drain and fills.
I have a 680C which I bought and used as a dozer for a while. That paid for it twenty times over. Now it just sits around most of the time. About 10 years ago the manual transmission locked up so i pulled it out. It was totally full of water. Can it be the shift boot because the work station is covered? It is the only way as mentioned. Tore it all down and found nothing wrong. Put it back together with new seals. Seamed like the countershaft bearing locked up like a one way roller clutch. I may have replaced those roller bearings but I found nothing wrong other than it was full of water. Have a 680E apart right now. No way to drain the converter in the machine but I thank that is unrelated to the question. Anymore I just loosen the drain plug and check for water if it has been parked a while.
I dunno, strange things happen to machines that make no sense. A four speed transmission with a good pliable shift lever boot in place should never get water intrusion. Especially with a cab over it. That is just weird. In regards to draining a 680 convertor. If the oil is really nasty removing the shuttle and convertor will give a person a way to drain it. Remove the convertor and turn it with the input shaft opening over a bucket and drain it. I have done it that way myself. A side benefit of doing it that way is you have an opportunity to inspect the flex plate on the flywheel. This photo is what mine looked like when I removed the engine. It was on the brink of failure. It probably would have broken completely with the machine in a very bad place.
"on the brink of failure"..?? LOL.. Holy smokes..
I was lucky on that one considering the machine weighs 7 tons. Factor in a 1 1/2 cubic yard front bucket full of material and then the rolling resistance on soft ground. Good Grief !!!!
Did the torque converter pilot break off like this one did?
Ha ha by saying that you really pushing my mechanics skills to take the torque converter off Tinkerer : p hence that flex plate photo looks scary and i can only hope mine would be in better shape. The machine has clear signs that gearbox, shuttle and axles have been reconditioned some time ago though not sure about the quality of workmanship or how much things have been in use ever since. Managed to change all the gear fluids and it runs again, decided not to use diesel for flushing will do more frequent fluid changes instead. From the shuttle i was able to drain approx 8 litres out by also disconnecting the cooler lines. According to the specs the system should hold 11.3 litres which is i guess good enough if i will do another oil change shortly, same thing with the gearbox. Here is another shot of the improvements at the airline side, added a mini pressure gauge to monitor the pressure in the hydraulic tank.
No, the convertor was ok. The small amount of flex plate that was left was still working with no vibration. Squad, it was a good idea to replace the air pressure gauge. It had one there when the machine was new. The service manual says you must have air pressure in the tank to prevent damage to the hydraulic pump on start-up.
The converter is a bit expensive. We fixed the old one. The C does not have air and I did not notice that gauge set up on the E. Should it be 12 PSI like the picture?
Yes ; air pressure should be 12 to 15 PSI. Tenwheeler, If your 680C doesn't have air brakes it is a series B. To clear up any confusion the correct way to describe your machine is ---> 680C series B. They were made from 1969 to 1970. In 1971 the B series was discontinued and the machine became known as a 680C.
Strewth ! With all those shiny new parts it is going to be too good to get dirty from all that dust our Climate (globally warmed that is) delivers these days; Can't follow a Kelpie across a paddock a day after rain now with out dust / sadly. Best of with the build; Fun and production there for sure.
it has been a while but there has been some progress, almost finished overhauling the whole rear arm of the backhoe. it was quite a mess when i got the machine at first, most of the hydraulic tubes were gone and replaced with whatever hoses they got. recreating the tubes was not easy or cheap to do as everyone is keen to make hoses hence there are very few places in here where hydraulic tubes can be done using small radiuses as it has. also stabiliser cylinder seals have been replaced and it was a decent challenge to get the lower pins out as there are no grease zerks to keep pins in play. eventually i give up and cut them off from the pads and made a new ones, old pins were so seized that guys from the workshop had to use 200+ tonne press to push the remaining pieces out. other than that it is coming along slowly and surely, there is still some work to do, new tires, new paint to rims are and cab needs to go back on as well after small overhaul and patch up. added some photos of the progress as well.
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Looking better and better Squad ! Nice job on the pipes.
Time for another update, managed to fix-up the cab over the Christmas, had to cut out and replace the whole bottom part as there was not much metal left, sandblasted it as good as i could and then painted with 2 two pack polyurethane. I had some spare polycarbonate sheeting and covered three openings using windscreen seal with locking strip, i must say it is such a tedious job and easy to get sore fingers for a next day or so lol. Also i figured that transmission temperature gauge has been somehow missed out when the dashboard overhaul was done, took some time and fabricated it to the set, looks little too modern as separate unit but at least it is there now. Another milestone was the new set of tyres, both front and the rear. Tyre fitters from the shop recommended to go tubeless hence after seeing how little coverage the sealing bead has, especially what rear tyres have i hope it was not a mistake and i do not have to put the inner tubes in, will watch and see. Had some trouble to get the rear rims off from the hub as they were totally rusted in, after soaking the area around the hub with wd40 for a day i got rims off using 2.5m pipe and sledge hammer hitting the rim from the back across the other side of the machine. I managed to get second hand skid steer rims 12-16.5 with matching bolt hole pattern, they are half an inch bigger in overall and slightly wider but it gives much better selection of tyres to use, including R4 pattern, the cost of tyres is lower as well. Some shots from the site added as well.
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Looks awesome !
Looks good
Thanks for that Tinkerer and Coy Lancaster . I got some more stuff to add, hopefully it is somewhat valuable. During the last couple of weeks I ended up with four leaking hydraulic cylinders, therefore decided to repack things by myself, half of the total has been previously done hydraulic workshop, basically another half to go. The first one to deal with was the big one off from the dipper, it has been on the edge for a while until last week when it kind of really gave up and started to run badly. I do not hold much faith into those ebay gland wrenches and therefore made the custom ones out of scrap metal. For this machine four different sizes are required, maybe five if extendahoe cylinder is different again. If anyone needs a CAD file of the gland face surface to make a tool I am more to happy to share the link. Given the almighty gland tool I made to get the dipper cylinder gland moving, it was actually already loose and did come off right away, cap nut was a challenge. With first attempt using breaker bar and impact wrench had no luck, there were some stains around the bolt and instead of using more leverage i heated it up with propane torch to 250 ° C and that was a win, though those stains were all loctite red, should have been blue. Another cylinders to do are the pair of swing and loader bucket cylinders, I have not worked with those yet only tried to get the glands moving, all good except right loader cylinder, bent the pin from the tool and still no go, probably will weld a plate to the gland and try to hit it with the hammer. Also I have to replace both rods of the loader bucket, does anyone know are 1045 grade, induction hardened chrome rods the right ones to use?
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gland layouts in CAD format for Case 680G
Had a lucky day today, as i started to look how to replace some backhoe linkage bushings and when removing the bucket and linkage arms i noticed some decent back and forward play of the bucket cylinder rod, not good. After taking the cylinder apart the piston bolt was literally hanging by an half a thread inside the rod. Apparently the bolt has become loose previously as well as piston was quite beaten up, barrel must have been replaced as it looked all smooth and fine, threads inside the rod were not too bad either. Perhaps someone with more experience can comment, would red loctite and 30% reduced fastening torque be better or worse compared to blue threadlocker and torqued to specs as per service manual. I figured that was done by someone when i was resealing the dipper cylinder, red loctite and likely 750ft lb torque with 3/4 impact wrench, which is approx 30% less as in specs, manual says 1000-1200ft lb. I guess the logic behind of that is it does not need that much force to get things assembled and undone, hence using heat.
I always use red Loctite and torque to as tight as I can get it with 3/4" drive torque multiplier and a cheater pipe.
I do not have a manual but have done some of the cylinders on my 680 several times over the years. Used whatever color loctite I had a 3/4 impact, maybe a 1 inch on the larger hoe cylinders or a 1/2 on the steering cylinders. Never had a problem with that. More concerned about loctite mucking up the threads taking it apart. If you heat the nut to about 350 degrees F I thank that is enough to melt the loctite and not hurt the metal. Sounds like Coy does things more proper than I but that has worked for me.
I don't know about more proper I just find what works for me lol
Thanks for the comments, i am leaning towards using red loctite and the impact wrench from here, also ordered half an inch longer bolt for the bucket cylinder for additional assurance. Started to work with backhoe bucket linkage bushing and it is a mess, quite a few are trashed and there are couple of missing ones as well, got some 4140 hollow bar stock for machining shop to begin with.
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Looks like you might need a new piston. You might be able to clean that one up though.
I will try to salvage this one if i can, will let machine shop to straighten out the seal grooves and hopefully it works. I got old bushings out from the small parts of the bucket linkage, there were couple of missing and most of them were loose. Bushings on the bucket side of the extendable dipper were all loose and the lining housing is slightly elliptical, not great. I was not quite prepared for that but I guess the proper thing to do is to slide the dipper arm out, take it to the workshop and let them to fit new things in.
I don't suppose you have anyone that has a portable boring machine. That way you wouldn't have to take it apart.