580ck shuttle/converter

[samk]

i have a mid 60,s 580 deisel that i got 3 months ago and have been working on ever since. initially pump pressure was low and the unit would only nudge itself. i pulled the valve body off and found the screen pretty clogged. checked the spool and relief valves, put in new gaskets and put it together.i now have 300 psi and the outlet port of the filter and converter pressure with all in neutral sits at 38 psi. this is where the problems start. shuttle pressure with all in neural sits at about 150 but drops to 100 and even lower as the tractor warms up. the converter pressure drops to about 18 with the shuttle engaged [no difference whether in forward or reverse], but swings back to 38 with the shuttle in neutral. the thing appears to run ok for quite a long time with the backhoe removed but a lot less when it was on[probably the extra weight] and then the slippage starts. things that i find strange is that the shuttle pressure drops to 0 whenever the clutch is depressed and my case manual states that it should be about 30. what i am trying to do is to isolate the problem to either the shuttle or converter. any and all assistance is welcome sam

 

[Phil]

Sam,
I like the way you've presented your problem, lots of detail. I'd like to focus on your dash gauge pressure first, falling off when warm. You obviously have a more accurate gauge in place of it. Would you check the dump valve adjustment; 3.1" from the center of the cam follower bearing to the center of the rear 1/4"NC bolt that holds the cam follower bearing support, on. Check with clutch released(foot off). Check that the clutch pedal returns to it's stop, after you take your foot off it. Just a basic check.

Disconnect the 2 lines going to the front cooler/filter and blow through them. looking for any restriction to flow, a collapsed hydraulic hose, plugged cooler, or restrictive filter. If you haven't already replaced the filter, then replace it. I have a NAPA # if you need it. Satisfy yourself that this part of the circuit has no flow problems.

Where in Ontario are you? Phil

 

[samk]

first of all phil thanks for responding and to answer your queries. first of all i was not sure of the dash guage so i temporarily hooked up another one for the shuttle and one for the converter so that i could see what was happening. the clutch is set at 3.1" as per manual and is retracting. the filter has been replaced and fluids renewed. i am in the little town of loretto about 20 miles south of alliston ontario. sam

 

[Phil]

Been thinking about your problem today. This copied text is interesting.
"With the control valve flow spool in the engaged position"( foot off clutch pedal)"the oil flows around the flow spool through a passage to the pressure regulator valve. The pressure regulator valve regulates the pressure and flow of oil to the power shuttle control spool" (gear selector spool) "and passes the remainder of the oil to the torque converter."

Pushing the clutch pedal down and losing all converter charge pressure just does not make sense. I have to read up on this a little more. Try blowing compressed air through cooler/ filter line assembly, also do you have the part # for the upper valve body gasket that you used? Phil

 

[samk]

i am in complete agreement on that . i have already blown compressed air through the lines. with regard to the gaskets i do see in my parts diagram that there are two different ones and unfortunately the info has already been tuffed but i can go back to the dealer and get the info. phil i know that i checked the serial #,s prior to ordering but that is not to say that i got the correct ones. i will find out tomorrow and let you know as if that is the case it could explain a few things.when the clutch is depressed i lose not only converter pressure but shuttle pressure also. thanks a pile for your input sam

 

[Phil]

Sam,
Just curious how your pump looked when you had it out, did you take it apart? Are you able to get on CNH to look at the parts for your tractor? If so you can verify the gasket part #'s for your tractor. Have you had the converter pressure regulator valve apart? Have you had the clutch pressure regulator valve apart, did the springs look okay? Still guessing, Phil

 

[samk]

well phil, when i pulled the shuttle valve body to clean the screen i did indeed take both the converter aND SHUTTLE PRESSURE REGULATING VALVES APART and checked for spring length etc . and all was fine . i also at this time pulled the pump apart and checked the relief valve and all looked good. you did however give me something to think about and that is the two upper gaskets on the valve body. my parts book indicates that after a certain tractor serial number that these two changed as they have a different parts number. the thing that i am now wondering is whether or not i have the right two as the serial number on the tractor is long gone. . from what i have read also is that the upper one could be placed either way. my case book shows the 2 upper gaskets as A37544fot the oil distribution plate and A37545 for the control valve on tractors with serial numbers prior to #8314666 and A38029[oil distribution plate] and A38030 [control valve] after serial # 8314666. right now until i find my invoice based on the fact that the serial # plate is gone i am really not sure which ones went in . hopefully if it,s not pouring rain tomorrow i will pull the top off the valve body and see. keep the ideas coming sam

 

[samk]

the trouble may well be elsewhere phil but i am reluctant to split the tractor ontil a probable cause lines up with all the symptoms. right now i am going to check out the gaskets. what do you think? sam

 

[Phil]

Sam,
I just noticed, in my CK service manual, the change starting at serial #8314666. Apparently the converter is dumped in the neutral circuit prior to, and charged in the neutral circuit after 8314666. This will explain part of the puzzle, as you probably have the prior design, however I have run out of time, talk to you later. Phil

 

[samk]

phil, pouring rain today and shop is full. i did however find a part # on the upper valve assembly that i have not been able to find in my parts book . it is A38032. are you able to line it with anything as i think if i can nail it down i should be able to determine the correct gaskets sam

 

[Phil]

Sam,
Just to go back and answer one question you had, with the early model, pre 8314666, you will lose shuttle pressure when depressing the clutch pedal, same as in later models. Usually the clutch pedal doesn't have to be moved far to see the pressure drop and as you can see by the cam, the 'flow spool' moves forward quickly at first. I am still suspicious of the setting of this spool, as it would explain some loss of oil if not adjusted properly. Would you go back and adjust this spool out(to the rear) a bit more, maybe to 3.2"? I use a very long 1/2"extension with a universal and 3/4"socket to reach the nut on the cam pivot bolt. As you probably know the bolt has an eccentric on it. The roller bearing and bolt connecting the roller to the spool tends get loose and not one of Case's better ideas.

I can't get on the Case site this morning, so I can't check your upper valve body # to verify it's an early one, or the gasket #'s. Phoning your Case dealer and asking for info re your recent gasket(s) purchase, should get you the # of all 3 main gaskets that you replaced.

I can post a picture of the later upper gasket if you wish, as I now keep all 3 gaskets in stock, for fear of them being discontinued, and losing the pattern. I guess now I will have to get another.

Did you replace the 2 seals that go under the pump when you had it off? Phil

 

[samk]

phil,the problem that i have is that the old gaskets were tuffed so i am not 100% sure that i have the correct ones in. as previously stated the tractor serial # is long gone and the only thing i have to go on is the upper valve assembly # of A38032. as for clutch adjustment i have already tried moving it out some with no change and the oil pump o rings were replaced. i have no idea if incorrect gaskets could cause some of my problems but that is a place to start. i have had no luck connecting with cnh as it appears they are off line. what i am trying to do now is to determine which gaskets belong to this valve assembly.

 

[Phil]

Sam,
I was able to get on CNH tonight:
http://www2.casece.com/wps/portal/c...CaseCE&brandsite_language=en&brandsite_geo=NA
Click on 'Launch Parts Catalog', when the CNH page loads, type in 580, go down to 580Case Construction King, scroll down to 096(late) or 097A(early).
I was able to find the reference to A38032 valve as part of a valve assembly, probably only available with fitted spools. This was on the early 097A page, pre serial #8314666. The early 3 main gaskets are from top down are A37545, A37544, and A37517.

On page 096, serial # 831666 up, the late 3 main gaskets are from top down are A38030, A38029, and A37517.

The converter relief valve gaskets are the same on both pages.

I think you have the early model and need 2 early gaskets A37545(top) and A37544(middle).

Your Case parts guy should be able to go back on the computer and tell what gaskets you bought. They are usually pretty helpful. Try a call.

I posted a pic of the pre 8314666 shuttle valve page.

I noted that the pressure regulator valve uses a double spring on the later model and a single spring on the early model.

I went back and read your first post and want to re-confirm that the 'dash' gauge pressure falls as the machine warms up, when in neutral, not when in forward or reverse. Phil

 

[samk]

well phil i went out today and rechecked every thing and results are as follow,. With engine cold and about 1500 rpms with clutch engaged and shuttle in neutral pressure is 150 psi. With clutch depressed it is 0 psi. With clutch engaged and shuttle in forward or reverse pressure is 110. with clutch engaged and shuttle in neutral converter pressure is 38. and 0 with clutch disengaged. with engine fully warmed up pressures are as follow.. With clutch engaged and shuttle in neutral pressure is 150. with clutch engaged and shuttle in either forward or reverse pressure is 80... so between cold and hot it drops at least 30 psi. the one thing i might mention is that it starts slipping in 4th a lot quicker with the backhoe on.. i am still not clear why the pressure in neutral drops to 150 when it is isolated from the clutches etc. a friend suggested that it might be worn seals or worn sealing rings in the torque tube area. i have taken the assembly off and the gaskets appear correct and i have taken pictures but do not know how to send them to you sam

 

[Phil]

Sam,
If you could clarify this: "i am still not clear why the pressure in neutral drops to 150 when it is isolated from the clutches etc".

If you mean the drop in pressure, from the test at the converter filter(300 psi), that's the pressure regulating valve doing just what it's supposed to do.

I may have got confused right from the first post on this problem. The same dash pressure both hot and cold, in neutral, with foot off the clutch. That is good.

You can add shims(flat washers) behind the pressure regulator valve, to bring this up to the spec. 170 -190 psi, the next time you have the valve assembly off. Let me know if you want a 'thickness' dimension.

At low idle, you should have the same pressure, it doesn't need to be at 1500 rpm in my opinion. That dash needle should never change Sam, hot, cold, high / low idle, as long as the foot is off the clutch and it's in neutral.

Now we can move on; you probably have the correct gaskets too.

In forward or reverse: cold you have 110 psi, and hot 80 psi. The difference is because of oil viscosity. The drop in pressure is not good and is most likely in your clutch packs, not your converter. Yes it can be leakage in the 3 housing rings that direct the clutch apply oil into the shaft(or valve body gaskets). But there are many other places to leak, usually in the clutch packs.

In my experience, just because it's the same pressure drop in either gear, doesn't mean the problem is not in the shuttle clutch packs.

If you've been easy on the machine and not slipped the clutches too much they most likely will be alright. They are quite robust. Hopefully you have a Rockwell shuttle. Let me know if I have interpreted the info your last post correctly. Phil

 

[racerx]

New to forum

samk,
sorry to impose on you & phil. I'm a total newbie unable to start a new thread. I'm looking to purchase my first backhoe - for ditch digging, timber clearing, bridge building with corrugated pipe across a small stream, filling in an old swimming pool, etc...etc.. on 12 acres of ground. I have my eyes on a 1987 Case 680K 2WD machine, up for sealed bid by a local municipality. It has 6250 hours, and has been owned by this municipality since new. I talked to the head wrench at the shop where it is kept, who has worked on the machine for the past 18 years. No major problems to report, and he showed me the maintenance history files. From what I can research, this machine was only made for 5 years? Any feedabck on the 680K would be appreciated. What would a '87 680K in good condition be worth? She is one Big machine, but I believe I have the room to use it.

 

[samk]

well phil, it is correct that pressure in neutral does not change hot or cold regardless of rpm,s but i should clarify that the pressure when the tractor is hot and in gear at low rpm,s [700] does drop as low as 60 but as the rpm,s pick up it goes back to 80. by the way do you know how to post pictures as i have the assembly apart with pictures. thank,s for all of your help

 

[Phil]

Sam,
Sorry if I sounded blunt in my last post, these units are labour intensive. I've made a few mistakes with them in the past, and don't want anybody to be fooled like I was.

Dropping to 60 psi in gear, hot, at low idle is not unusual, I have seen them with no pressure showing on the gauge. The shuttle pump in my opinion actually supplies far more oil than needed to make up for minor sealing ring leaks, and I have seen quite a few with visibly worn pumps, still moving the machine.

Pictures have to be shrunk a little to post. I will PM you with how I do it, so as not to get off topic on your thread, please check your mail.

Racer,
I'm not familiar with the newer 580 or 680 models, so I can't tell you about any inherent problems. Check the 'machinery trader' online, for an idea on machine value. The hours sound okay, probably work good for you, certainly a powerful machine. The upside is the verifiable background, the downfall is that it's a 680, not popular when reselling, it's heavy, only 2 -wheel drive, and used/aftermarket parts are much harder to find. It could last you for years and years, might be a problem with it so if you could talk to an operator who has used it recently.......Phil

 

[samk]

Photos

Here are photos , can you make any sense out of them?
Another photo in next message.
Sam.

 

[samk]

1 more photo.

Heres' my last photo.

Sam