How to Rebuild the Backhoe Control Valves - 580CK with Model 33 Backhoe

[1968 Case 580CK]

I have my 1968 580CK restored and looking pretty good, but have not started the backhoe rebuild.




Last weekend I went to move a bucket of sandy soil without the heavy backhoe attached and the rear tires are getting very little traction since the weight of the front loader is acting like a sea-saw with a fat kid on one end and little varmit on the other end. I was spinning tires, and had to off-load half the bucket before being able to move the dirt.

So, I realized that I need to rebuild the backhoe Control Tower/Valves pronto so I can mount the backhoe and again have good weight on the rear tires.

Here is a pic of the Control Tower that I need to replace alot of the ORings. Can someone give me any tips/suggestions before I tackle this job? After removing the metal cover (in pic), do I just take the next bolt off, and then extract the entire assembly? I have all the ORings (thanks to Dale at Tractor Stuff) needed to do the rebuild, but was hoping to get some good advice before diving in.





Thanks.

 

[mikebramel]

Remove the spool cap as in the picture, then you can pull the spool out of the bore.

 

[1968 Case 580CK]

Remove the spool cap as in the picture, then you can pull the spool out of the bore.

Mikebramel.....thanks. How about the larger "check valve" nuts/caps on the sides......you can see a row of 6 of them in the first pic.? Do you think it is worth the risk of screwing them up to remove and inspect/clean? Do I need to remove them in order to slide out the longer spool that comes out from the top?

Thanks.

 

[melben]

When resealing the spools be sure to put the o ring on the spool instead of in the body, if the spool is shoved through the o ring it will shave the o ring rendering it worthless. Often the spools are scored on top and all you can do is polish them as good as you can usually you will get away with it. If you are going to split the valve sections to replace the section o rings clean the area perfectly clean. Do not over torque the tie bolts or spool binding can occour. Secondary relief o rings should be changed and if you suspect any to be faulty a good Case dealer has a fixture that your valve and seat can be installed in and bench tested for leakage and proper pressure. IIRC the operating pressure of the secondaries is stamped into the cartridge body.

 

[1968 Case 580CK]

When resealing the spools be sure to put the o ring on the spool instead of in the body, if the spool is shoved through the o ring it will shave the o ring rendering it worthless. Often the spools are scored on top and all you can do is polish them as good as you can usually you will get away with it. If you are going to split the valve sections to replace the section o rings clean the area perfectly clean. Do not over torque the tie bolts or spool binding can occour. Secondary relief o rings should be changed and if you suspect any to be faulty a good Case dealer has a fixture that your valve and seat can be installed in and bench tested for leakage and proper pressure. IIRC the operating pressure of the secondaries is stamped into the cartridge body.

Melben......Thanks again for your input. Here is a pic of the first valve/spool shaft pulled out:



The metal retainer and its ORing are pictured as they have slid down from their position up near the spring end. Are you saying that it might be a good idea to "polish" the upper portion of the spool shaft (the end that connects to the levers on the control tower)? I will check each one and do as needed.

Here is a pic of the spool shaft with new ORing beside its metal retainer, and with a light coat of grease on the shaft and ready to slide in.



You can see that I do not have the top ORing on the shaft. Instead, I had removed the old one from the body, cleaned the area real good with diesel/toothbrush/Q-tips, then put some oil in the Oring groove, oil on the new Oring, and placed the new Oring into the valve body. I cautiously slid the greased shaft from the bottom end and up and through the new Oring at the top. A little pressure on the spring end of the shaft, and the bottom Oring then popped into place. (This works as long as the upper end of the shaft (the slotted end) has not been spread apart or is damaged). Seems that if I put the upper Oring onto the shaft, and slid it through all those resistance points in the valve body, it would be more likely to get damaged.......so, you think that the way I am doing it will work?

The only hydraulic leaks were at the top of these spools where they connect with the linkage to the operating levers. So, I was hoping to just remove the 6 spool shafts and replace the two Orings on each one. Do you think it necessary to take any of the other shafts, relief valves apart? (Backhoe was working fine, except for the leaking at the top of some of these 6 spools).

Thanks.

 

[melben]

Yes , perfect, Took it for granted that you would know the top ring went in the body prior to installing the spool. yes, polish the spools to give a good surface to seat the oring on

 

[1968 Case 580CK]

Yes , perfect, Took it for granted that you would know the top ring went in the body prior to installing the spool. yes, polish the spools to give a good surface to seat the oring on

Melben.......10-4, got it. First time I have ever performed this operation, and it seems pretty straight forward. Gotta get the old hoe put back on the tractor so I will have some traction while lifting logs. (I just picked-up a good set of lifting forks that fit on the loader bucket, and am looking forward to wearing them in a bit, and without the rear tires coming off the ground).

 

[thepumpguysc]

Well done sir..
When my buddy got his 580, some of the controls for the bh were frozen to each other.. when you went to move the bucket, the stabilizers would go up or down.. lol.. that was fun to figure out.. I ended up removing the whole control unit and cleaning it up and replacing the zerks.. lets just say, that control unit hadn't seen any lube in YEARS..

 

[1968 Case 580CK]

Well done sir..
When my buddy got his 580, some of the controls for the bh were frozen to each other.. when you went to move the bucket, the stabilizers would go up or down.. lol.. that was fun to figure out.. I ended up removing the whole control unit and cleaning it up and replacing the zerks.. lets just say, that control unit hadn't seen any lube in YEARS..

the scpumpguy.....Thanks from the guy a "little south of tha border"......at least thats the sign I see on 95 while driving from Va to SC. Just hoping I can put this valve assembly back on and have no leaks. Yep, that must have been driving you nutty with the valves frozen to each other......all kinds of wierd things must have been happening when you pushed those levers. Yea, I also have a couple zerks that are broken off, and I need to put new ones in and grease her well.

Watch out for those crocs down there in the SC outback!

 

[1968 Case 580CK]

Do you need to prime this valve assembly after rebuilding?

In the last picture above, you will see a plug on the right side of the assembly. There is also a plug on the other side. Is it a good idea to first mount this heavy valve/tower assembly back into the backhoe body, and then open the two plugs and use a funnel to fill her up with hydraulic fluid? Seems this would reduce the amount of air surging back through the lines and bubbling up in the main resevior. Is this why the two plugs are there?

Thanks.

 

[mikebramel]

No, open center design. Self bleeding. Constant flow from pump to valve to tank

 

[1968 Case 580CK]

mikebramel.......Ok, self bleeding. I wonder what the two pipe plugs are for on each side?

 

[mikebramel]

1st guess - gauge ports. 2nd guess - to clean the casting out. Happy thanksgiving

 

[1968 Case 580CK]

mike........yea, thats it.......for screwing in pressure gauges to check the various pressure readings. Also for flushing out the casting......man, your good. You too....happy Tgiving/Christmas.

 

[1968 Case 580CK]

OK......I got the heavy valve assembly rebuilt, and began the job of installing it back into the backhoe body, and hooking up all the hoses to it. I was thinking that this would be a pretty straight-forward job, but I must say it was a pretty difficult job, as I will describe.

Here is a pic of the valve assembly mounted back into the backhoe:





It was quite a puzzle to decide which lines to install first so that my large "crows-foot" wrench could torque down without being hindered by another line, or general "stuff" in the way so as not to be able to get the wrench on to do the tightening. I figured that since I was turning "clockwise", that I should start on the left side and work to the right......bottom row first, then the top row.

This process seemed to work, but I had to loosen a couple in order to shift around the lines and the hard "U" shaped metal lines in order to get the mess to come together in a workable manner. The Crows foot sizes were 1 1/4 and 7/8 on the smaller ones, and I believe 1 1/2 on the two large outer lines (feeder and return to pump).

I thought I had them all torqued down good, but after the long process of backing the tractor back into the backhoe, attaching the quick-disconnects, and struggling to get the large upper pins in place, I then realized that 2 or 3 of the lines were leaking where they screw into the rebuilt valve tower. I thought that I had torqued them real good, but they were loose. I believe that the large Crows-foot wrench was rubbing against another hose end, and stopping the wrench......so I thought it was torqued good, but it was actually still loose.

I had to pull out the pins and disconnect the hoses and pull the tractor forward to make room to tighten the hose ends. Had to stop because of rain.

I am wondering if Case has an exact method as to what is the best order for installing/tightening these hoses. Do you start on the left side and work your way accross, one row at a time. Or do all the larger 1 1/4" lines first, and then the smaller 7/8" last (since the wrench is easier to find room and fit on the 7/8" hoses).

Also, the tractor mounts are fixed and do not move.....so, when backing the tractor into backhoe, there is very little tolerance. Then, getting those large 1/4" thick washers in place along with the big pins is a pretty frustrating process. I assume you have to just do one side first and then use a combination of the hydrualics to lift the backhoe up/down/sideways to get the last pin/washer in. Are there any good tips on this process?

Does Case make a specific type of crows-wrench that is narrow and turns without running into the adjacent line?

Any suggestions would be appreciated.

 

[1968 Case 580CK]

Also, I believe I read prior posts where someone was removing this backhoe valve assembly, rebuilding it, and putting it back on WITH THE BACKHOE STILL ATTACHED TO THE TRACTOR. I can only say that this person must have been the most patient person in the world, and probably a shape-shifter......to get around in that cramped/confined space and pull off this miracle. I found that just trying to tighten one of the upper lines had me contorted and twisted up under the seat and fussing and cussing way too much......so, the only solution was to disconnect and move the tractor out of the way.

I applaud that person who said he had performed this job with the backhoe attached to the tractor.

 

[mikebramel]

Don't know the specifics of this one. But, I usually start in the center and work out. I put the crowfoot wrenches on a 1/2" drive 24" locking flex head ratchet. OR combination wrenches with a hammer tap. OR angle wrenches with a hammer tap. .... aren't you going to need more tools for your next project? LOL

 

[onemank6]

Hi 68case been watching your post's on your tractor i have a 1970 ck and for 3 years now have been making repairs to it while using it this winter im doing a split on it to give it some new clutches/seals/gaskets it has been a ongoing process since i have owned it i might even throw some paint at her this winter?/ Anyway i just helped my neighbor with his we pulled the control valves and had someone reseal them for him then we installed them back in the backhoe and yea kinda a pain.We installed the lines from left to right put the bottom on first then the top working toward the right and used straight wrenches it was kind of like doing a puzzle but went alright. Also looking at your last picture i cant see any rubber dust boots on the top of your spools they go between where your control rod pins to the spool and the top of the valve body. I think one of the reasons these start leaking in the first place from the top is because dirt gets in from the top of spool and tears up the o-ring at the top of the spool so if yours are not there you might look at getting some for it. My 70ck had leaks on the top when i got it to and there was a lot of dirt around mine when i bought i have since fixed the leaks and am always keeping that area sprayed out from dirt. Anyway yours is looking nice and keep the info flowing its good stuff..

 

[1968 Case 580CK]

Don't know the specifics of this one. But, I usually start in the center and work out. I put the crowfoot wrenches on a 1/2" drive 24" locking flex head ratchet. OR combination wrenches with a hammer tap. OR angle wrenches with a hammer tap. .... aren't you going to need more tools for your next project? LOL

mikebramel......starting from the center and working out may be the answer. I think the problem is that the Crow-foot set I bought are designed a bit too big......and so, there isnt much movement before the crow-foot hits the hose nut beside it and stops. I was tempted to take the crow-foot to the grinder and take some off. I am using a fat crow-foot, an adjustable length 1/2 drive, and an extension to bring the adjustable wrench outward where there is room......its not a friendly set-up, and takes alot of patience. When I get to the 7/8" size hose nuts, it is quite a joy to pick up a straight 7/8" wrench and toss the crow-foot and accessories to the side.

Yep......I surely will need more tools for my next project. Problem is that I cant find the ones I do have.....I have a set of the nice Case Crows foot wrenches just for this job, but some dern crow probably flew off with them.

 

[1968 Case 580CK]

Hi 68case been watching your post's on your tractor i have a 1970 ck and for 3 years now have been making repairs to it while using it this winter im doing a split on it to give it some new clutches/seals/gaskets it has been a ongoing process since i have owned it i might even throw some paint at her this winter?/ Anyway i just helped my neighbor with his we pulled the control valves and had someone reseal them for him then we installed them back in the backhoe and yea kinda a pain.We installed the lines from left to right put the bottom on first then the top working toward the right and used straight wrenches it was kind of like doing a puzzle but went alright. Also looking at your last picture i cant see any rubber dust boots on the top of your spools they go between where your control rod pins to the spool and the top of the valve body. I think one of the reasons these start leaking in the first place from the top is because dirt gets in from the top of spool and tears up the o-ring at the top of the spool so if yours are not there you might look at getting some for it. My 70ck had leaks on the top when i got it to and there was a lot of dirt around mine when i bought i have since fixed the leaks and am always keeping that area sprayed out from dirt. Anyway yours is looking nice and keep the info flowing its good stuff..

xpackdeals.......Hey xpack....yea, we have essentially the same tractor, and have been going thru alot of the same repairs......and some have been real challenging for sure. Post some more pics if you have time.....and some before/after when you "throw that paint at her". If you want new "Construction King 580" hood decals, Dale at Tractor Stuff has all that for a fair price.

OK, you installed the lines from the left to the right (since your'e turning the wrench clock-wise, this makes sense).

Those rubber dust boots on top of the spools. I agree that it seems like a good idea to use them, but a mechanic at this site had replied in a post that he felt that the boots just trapped moisture and were not a good idea. But I tend to agree with you that keeping those fine particles of dirt away from those upper seals is more important. Maybe I will rig up some type of dirt shield above them, or something. I will also keep it covered so rain/moisture will not be getting to the valves.

Thanks for the input, and I look forward to seeing more posts on your progress.

Hey.......how close is your rear tire thread away from the backhoe stabilizers? I put new tires on, and now about all the gap I have can be measured with a set of spark plug gap gauges. One of the stabilizer lines is rubbing the tire, and I need to adjust that also. These are the same size tires that I took off, and I was actually considering going with the next taller size (which the Case manual says will work). Glad I didnt, as there is absolutely no more room back there. I might also have to try to add washers to the stabilizer pivot point so as to force it rearward as much as possible. Always a new challenge when doing all these repairs.