Thanks for the advice john. The engine behaves as described. I cannot lug the engine too much by pulling or pushing too hard with the hoe. I do not think however that the pump has different sections, one for the hoe and the other for the front bucket. There is only one outlet from the pump. It goes into the valve for the front bucket and from the valve oil goes to the hoe. Eric
Those EZ-Up tents are handy for working on stuff like tractors and backhoes if you don't have a shop that can fit them. Put down a tarp, drive the item onto it and then pop up the tent over the top.
Single pump, open center hydraulics. Not as high performance as a closed center system, but much cheaper and simpler. You can probably replace the pump entirely for a few hundred $. Of course before you replace the pump be sure to check the relief valve since if that has an issue it's like $25. I got a small tractor with loader that had poor hydraulic performance and all I had to do was clean and readjust the relief valve to fix it.
Maybe I'm a pessimist, but I'd be prepared to drop $3K or don't start. of course this is to get it back like new - rebuilt pump, new fluids, new filters, new guage, relief valve, and a few other gotchas that always come along (like hoses that will pop right away, cylinder seals etc). I've repaired a LOT of tractors and the costs are always high.
Karl
Can you divide them into more and less unreasonable?
Does having machine tools generally help? I made or modified steel parts for the pump, its drive, the relief valve, return manifold + strainer and cylinders for my homebrew but I had to buy the new piston seals and hoses and pressure-side fittings.
-jsw
Do it right, it is not that expensive.
i
I am willing to replace the pump, filters, and any hoses. That will be way less than 3000 frog pelts. I am not willing to drop 3 grand on the thing though. If you saw it, and knew how much I used it, you would understand. Eric
Greetings Pete, Where would I look for the relief valve? I mean on the machine. I can buy, and would if I needed the hoe right away to make money, a repair manual for about $250.00. But since this machinerepair is a low priority I'm willing to take some time and figure out what's what. Oh, and thanks for letting me know the hoe is open center, single pump. Eric
On Thursday, June 12, 2014 11:42:50 AM UTC-4, snipped-for-privacy@whidbey.com wrote: Over 30 years
I have no experience, but figure whoever was in charge of the lumbermill did. So I would grind the end plates to remove the scoring and see if that improved it enough for the use you give it.
Dan
On 6/13/2014 1:43 PM, snipped-for-privacy@whidbey.com wrote: ...
...
Why not? If it's otherwise in good shape, what would the replacement cost be for something you wouldn't (likely) have any idea of whether it was as good as the one you've got is?
I'd agree you should be able to get in and out for well under $3K, but (again assuming you do have the need for (or just seriously want :) ) it, would seem will within the expected of reasonable maintenance costs to me.
Sorta' like the old JLG 40H manlift I got off eBay for $5k when started the barn re-roof...it's now been almost 15 yr and I've put about $2-3K in it since, I'd guess w/o actually going back and looking at the actual books. The biggest single expense was paying to have the master cylinder rebuilt--it's a 20-ft long, 3" D(?) single-acting cylinder and I have no facility on the place to be able to get it out of the boom. Seems like the labor for it was about ~1200 iirc from the JD dealership (including them sending the float out to pick it up and deliver it). Pushed my luck and let a leaking head gasket go thinking we could finish the south side of the barn and have it closed to weather first and so ended up w/ a new head and pistons, etc., instead of just a gasket set that was about $500 could have avoided... :( But, like you and your 'hoe, it's been so handy to have that wouldn't consider just junking it over the cost.
Again, it depends on what one wants to do, and what on can live with. Our local electric co-op runs a side business of repair work for (primarily) truck lifts since they have so many of their own it keeps their guys occupied when there isn't one of their own needing work. They, being licensed and all, have to put everything back to manufacturer's spec's so thinking I'd give them some business I checked for the seals job on the lift. They cautioned me given the age it likely would end up at $10k or more because of all the ancillary stuff they'd see that would be out of spec...I'm comfortable it's safe as is and do inspect the chains and so on for any signs of wear but the manufacturer has a set of timed replacements or "replace all this if touch any of that" to cover their liability.
On 6/13/2014 1:46 PM, snipped-for-privacy@whidbey.com wrote: ...
You got a local Case equipment dealership? If so, make their acquaintanceship -- I'll bet they'll give you copies of any pertinent pages you need if you'll simply buy filters and so on from them.
You can, I'd almost bet, find exploded drawings online in the parts link I posted earlier. It's possible Case hasn't gone back far enough if your model is truly ancient but it's a high probability the newer ones are similar enough to guide you thru a bunch.
For comparison:
I spoke with two Case dealerships, one local and one out of state. Neither one could help me. One place had a service guy who had been there 40 years and he had never even heard of a gasoling powered 780 Construction King. Which is what I have. I had been to both of the places your links point to before posting. Neither had what I need. Apparently the diesel ones are different than the gas ones besides the engine. If you can find an exploded diagram you are a better searcher than I. Eric
Eric, your problem is an easy problem. You need to call hydraulics service shops in your area. For them it is not complicated to rebuild hydraulic pumps.
i
I have already called a couple and their advice was to just buy a new pump. I guess my pump is too small for them to consider. There is one place I still need to try though. Actually, I did try them but the guy I need to talk to is gone 'till Monday. Eric
OK, buy a new pump, they are not super expensive if you need a small one.
i
This is about a '78? We had both gas and deisel CKs at Advanced Construction WAY back. Can't remember anything about them though, other than the deisel was a better unit - the gas one was on the lot more the the deisels.
Almost always, they're on the pump body or on the main lever valve body.
In either case, look for a large "cover nut"... a hex-housing about 1-1/4" across the flats and about 2" tall. That cover hides and seals leaks from the relief valve adjustment screw, which is usually a female hex socket bolt/stud that you adjust with a large Allen wrench (seen a few slotted ones, too).
LLoyd
In all probability the relief valve is one section of a sectional control valve bank at the end of the circuit, probably the backhoe control. If you see a section in there that has no I/O lines going from it to a cylinder, yet it has a capped stem sprouting out the top or bottom, the relief adjustment is likely under that cap.
This type of hydraulic system is quite simple and if you browse a site with pictures of standard hydraulic components (Surplus Center perhaps) you should be able to take a notepad out and map out the system in short order. Particularly on an old machine, don't be afraid to Frankenstein it a bit and retrofit newer standardized parts in place of expensive Case specific parts. On an open center system this should be particularly easy.
Eric, you are probably way ahead of this but Toro has some nice basic instructional guides at
snipped-for-privacy@whidbey.com wrote:
In all probability the relief valve is one section of a sectional control valve bank at the end of the circuit, probably the backhoe control. If you see a section in there that has no I/O lines going from it to a cylinder, yet it has a capped stem sprouting out the top or bottom, the relief adjustment is likely under that cap.
This type of hydraulic system is quite simple and if you browse a site with pictures of standard hydraulic components (Surplus Center perhaps) you should be able to take a notepad out and map out the system in short order. Particularly on an old machine, don't be afraid to Frankenstein it a bit and retrofit newer standardized parts in place of expensive Case specific parts. On an open center system this should be particularly easy.
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