1997 Case 580 LE reverse wont work

Hi all, I’m hoping that someone may have some advice to my 1997 Case 580 LE with TLB1 shuttleshift reversing problem. The machine goes forward and 4wd perfectly. When engaged into forward it goes in within a second or so but sometimes might take 3 seconds, I have searched the forums and found similar problems but I’m hoping for possible answers. Some time ago, ALRman gave me some good advice which I have done, changed the transmission fluid/filters etc. and the electrics are working perfectly and have even replaced the solenoids. I can hear/feel the relays and solenoids clicking in but it’s a bit hard to determine the intensity or difference between forward and reverse on the solenoids. I had a mechanic come out and remove the modulator. He took it back to his workshop and said that the snap rings are ok and it was a bit sticky but didn’t think it would affect it working, he didn’t run a kit through it and I don’t know if he had bench tested it. He put it back on the machine and still no reverse. A few days after the reinstallation of the modulator, I was pulling the machine backwards with the bactor (pain in the backside) and reverse kicked in and worked perfectly for a few days then I noticed it was taking longer for reverse to kick in and the last time was about 10 seconds. Its back to square one with reverse not working again. Every now and again Ill put the machine up on the stabilizer, put in reverse and let in run for a while but still no reverse. The mechanic said he needs to check pump pressures on the tranny but to my way of thinking, if it goes into forward and 4wd without a problem, shouldn’t the pump do the same for reverse? The mechanic is talking about dropping the tranny and all I can see is big $$$$. Has anyone got any advice?

Welcome to HEF Brother! I would exhaust all other options before pulling the trans. There was a guy on here a year or so ago that pulled his backhoe transmission only to find out the problem was electrical. We have some smart guys here. Somebody will come along with some good suggestions.

Thanks JL I'm hoping someone might have a bit of an idea what's going on with my machine. It's a bugger of a thing because otherwise the machine is in great condition. Cheers.

Does anyone have any ideas?

If I were you, I would get the service manual for that machine and start troubleshooting. Sure it's possible there's an internal transmission problem, but would eliminate all other possibilities first. Have you inspected all the wiring associated with transmission control? It could be something like the F-N-R selector has a problem for example. I would check fuses also.

Be patient Brother.
The pros will eventually read this and offer some advice.

I'm assuming when you say the solenoids are clicking - these are the ones on the transmission control valve?
If the reverse solenoid is clicking when FNR lever is placed in rev - then you need to be certain that the small spool (32) in the reverse valve is actually reacting to gear selection.
If the spool is moving on when commanded (& hoping it has been fitted with the correct orientation) - & if the modulator spool is also free & been fitted correctly - then you will indeed need to look at pressure tests.
If the oil was very dirty at one stage due to a lack of servicing, it is possible that the charge pump is worn & struggling to supply enough oil to operate efficiently.
To test the charge pump you need to flow test it & that requires an adapter to install in place of the oil filter - even your CASE dealer may not have one of those.....
Chances are that if Rev is not engaging - you will read no pressure.
It will be important to compare any pressure readings from cold oil to warm oil - any big difference may point you to a tired pump.

Thanks JL and Tinkerer, I did get the workshop manual but it didn't help a great deal with trouble shooting. Alarman may have come to the rescue. Yes, the mechanic replaced the solenoids (the old ones were still ok though) and said he would do a pressure test and have a look at it at some stage. I'm trying to get my head around and understand this thing. When the mechanic removed and reinstalled the modulator, he didn't say a great deal other than the snap rings were ok and it was a bit 'sticky' (assuming he meant the spool), but he said it shouldn't have affected it going into reverse. The pump did cross my mind - If the machine was going into FWD and 4WD with no problems, would that mean that the pump is ok or is the reverse a separate pump? Sorry for the probably seemingly obvious questions. Thanks for helping, Cheers

There is only one charge pump - 3 seconds to engage fwd is considered a slight delay.
Technically, the reverse clutch pack shouldn't have the same amount of wear as fwd - for obvious reasons.
Doesn't mean though that it may have a reverse piston seal issue or shaft seal problem too - all only accessible from inside the transmission.

There will be springs & plungers inside item #2 - that are not serviceable - they maybe an issue as well.

In saying that, sticky spools can cause your issue as well. If some trash has gone through the valve there maybe some slight scoring causing the spools to "stick".
The FNR Direction spool is #32
Modulator parts are made up of #27; #25; #15; #38; #12

Once these things are confirmed as OK - pressure testing will be required to help diagnose the problem further.

Thanks Alrman, This is valuable advice. Ive ordered gaskets and O ring seals for the unit. I was given a quote for $1690 for a reconditioned valve modulator but my machine piggy bank (and the minister of finance) is starting to drain. I have the workshop manual that gives step by step disassembly/assembly instructions so over the next weeks Ill take the valve control modulator off and carefully take it apart and clean it it up and check for scores in the bores. I spoke to the workshop again yesterday and they stated that hey had a look and bench tested it and were ok with the idea of me going over it again and replacing gaskets etc, especially as it kicked back in to reverse after a day or so after the mechanic put the valve modulator back on. Ill get back after I have completed the clean up and see how it goes. Thanks all for the responses, its greatly appreciated.

Hi All,
A bit of an update.
Just another quick question. My Gear shift was sloppy and I could near spin it in my hand. I removed the gear shift control lever shaft and its housing and found a broken pin and the other was about to snap. The spring had no compression and the collar under that was also loose, I'm surprised it worked at all. I have since ordered the parts and waiting for it come in. Since Ive had the machine, the gear shift lever really didn't work and a local mechanic put in second gear for me and that's where it stayed. I still haven't fixed the reverse problem that brings me to another question. Because I I have not had the transmission in neutral, could this be the issue of it not reversing? So whilst it has been in second gear, I use the FNR on the column to move it forward (usually kicks in within 1 second) and just creep along in second. As I said before when the mechanic got the valve modulator off, it all of a sudden kicked into reverse a few days latter then stopped again going into reverse again. The mechanic has suggested that shifting through the gears might solve the reversing problem but I cant see how they are connected. Is there any chance that this might be the problem?

Ill keep updating as I go in case anyone else has these problems

Ive included some photos of the damaged pins and spring.


Broken and damaged pin


Damaged and new spring

In short. no, reverse/forward should work regardless of the gear selected.
That is a very sludgy looking spring, oil must have been pretty bad.....

Thanks Alrman, yes, the oil I drained was a honey colour and the filter contained a bit of crap but the sludge on the spring looked and felt more like grease. I thought that when the mechanic suggested gear changing might help, I couldn't see how that would have affected the valve modulator but I thought I would ask the experts here. Ill hopefully have the shaft reinstalled by next weekend then to part two of getting the thing to reverse. Ill pull the modulator as suggested before and give it a careful clean. Ill keep updating as I go. This machine seems to be a long term project but with all the rain here I couldn't really use it anyway without getting bogged

Cheers

Well, back again with this reversing problem that's driving me insane. I think the mechanic has given up on me so Ill battle on with any help from you good people here. Ive done everything short of dropping the trans, solenoids and relays all good and clicking, voltages on both solenoids 11.7v with machine off and trans full when operating with nice clean fluid. I just use the machine being careful not to get into a spot that I generally cant drive out of and if I cant, I just use the backtor to pull me in reverse, (I'm getting pretty good at now). I discovered by accident today by putting the FNR lever in reverse and free rolling backwards on a slope, it kicks into reverse and works backward and forward for a while. If reverse stops working, back to the slope I go, roll backwards once or twice and away we go again for about an hour. The forward on the machine is perfect, with no delays in switching or engaging, so I would imaging that trans pumps are OK. Does anyone have any idea at all what is going on with this crazy machine?

How about tapping the pressure test ports toward the rear of the transmission 6-8” behind the spool valve. I think the more forward one is for reverse. Get a hose and a 300 psi gauge and monitor what is going on and when. Without a good pressure check you will continue to be grasping at straws. If it comes down to pulling the transmission and shuttle rebuild, there are some good videos on Carraro transmissions on YouTube. They are not super difficult to work on.

I'm going to hop in here and offer a suggestion.

I had a similar problem with a John deere backhoe and it part of the issue was a bent solenoid. The piston or spring that the solenoid coil wraps around was getting caught up inside the mechanism.

If your key has a test mode (battery power is on), put that on and get a buddy to sit in the cab and flick the FNR switch forward and reverse. While he is doing that, put your hand on the solenoids and feel if they are operating and making a noise each direction.

It is a quick test, I know you said you replaced all your solenoids but the stem might be damaged.

Acecadet said:

How about tapping the pressure test ports toward the rear of the transmission 6-8” behind the spool valve. I think the more forward one is for reverse. Get a hose and a 300 psi gauge and monitor what is going on and when. Without a good pressure check you will continue to be grasping at straws. If it comes down to pulling the transmission and shuttle rebuild, there are some good videos on Carraro transmissions on YouTube. They are not super difficult to work on.

Click to expand...

Thanks for that one, I had a look at the spool valve and there are 3 small bolts that are for the tests . Its worth a shot to have them tested but the local Case mechanic here didn't have the right gear to do the tests and had to order one in, at my expense and the $$$$ started piling up.

Katherine A DeHaven said:

I'm going to hop in here and offer a suggestion.

I had a similar problem with a John deere backhoe and it part of the issue was a bent solenoid. The piston or spring that the solenoid coil wraps around was getting caught up inside the mechanism.

If your key has a test mode (battery power is on), put that on and get a buddy to sit in the cab and flick the FNR switch forward and reverse. While he is doing that, put your hand on the solenoids and feel if they are operating and making a noise each direction.

It is a quick test, I know you said you replaced all your solenoids but the stem might be damaged.

Click to expand...

Hi Katherine. Ive had the modulator off the unit and saw the little spring that you are talking about. I even thought at the time of taking out the spring thinking it could be the cause of the spool not coming all the way back to allow the fluid to pass by it and engage. I didn't take it out because I thought that the spring might have been a little buffer when the spool is pulled back suddenly by the reverse solenoid. Ive done some listening with a mechanics stethoscope to the spool. Going forward is a loud click and reverse is mixed, some loud some not so. I might be wrong but I thought that the free reversing down the slope my be forcing fluid through the spool that is enough to shift it from its stuck position. I think that I might need to concentrate on that spot. Its a pest because otherwise its a good strong reliable machine. Cheers

Is part labeled #2 on the diagram posted by ALRMAN above functioning properly? That has an internal plunger inside that is activated by your solenoids.

Brother100 said:

Hi Katherine. Ive had the modulator off the unit and saw the little spring that you are talking about. I even thought at the time of taking out the spring thinking it could be the cause of the spool not coming all the way back to allow the fluid to pass by it and engage. I didn't take it out because I thought that the spring might have been a little buffer when the spool is pulled back suddenly by the reverse solenoid. Ive done some listening with a mechanics stethoscope to the spool. Going forward is a loud click and reverse is mixed, some loud some not so. I might be wrong but I thought that the free reversing down the slope my be forcing fluid through the spool that is enough to shift it from its stuck position. I think that I might need to concentrate on that spot. Its a pest because otherwise its a good strong reliable machine. Cheers[/QUOTE

Click to expand...

Katherine A DeHaven said:

Is part labeled #2 on the diagram posted by ALRMAN above functioning properly? That has an internal plunger inside that is activated by your solenoids.

Click to expand...

When I bench tested it it seemed to move freely but that may change under pressure when the machine is on. I'm now thinking to take the tube off one more time and have a closer look to see if these is any discrepancies in the tube itself or as you said, if it is slightly bent enough to prevent free travel from time to time.