Tractor was driving just fine As some point the Shuttle Transmission became slow to engage until oil pressure built up Problem fixed by "topping off" lost oil with "Tractor Fluid" Oil leaking into Bell Housing (caused the teardown) Completely drained shuttle, torque converter, bell housing Removed Engine/Shuttle combo and separated (followed Case shop manual instructions). Shuttle input pump outer spline was stripped/gouged (shop said converter trashed inside) (I don't know how it still drove with no symptoms) Installed new input pump and splined shaft and new seal; added gasket sealer to large rubber gasket at pump base Installed new torque converter, did not perform any centering, didn't feel much "play" Re-coupled engine/shuttle trans; no problem, slid in easy with slight trans rotation to align spines. Re-installed engine/shuttle in tractor, connected all hoses, and wires (that I could find places for) Engine started right up Added 3 qts "tractor fluid" to shuttle through dip stick tube per shop manual, and started engine Began to add 4 more qts (per manual) with engine running, but dip stick tube overflowed with less than 2 qts added Seems input pump is not filling the torque converter Siphoned out some oil thinking I had an air bubble in the trans or fill tube, but no change in oil "take up" and no F/R Wondering if I needed Hy-Tran instead, as I've read in another thread here? It seems like the input pump should work on any oil, at least to fill the torque converter which I assume would allow the system to take up the specified amount of oil. I did not measure the length of the drive tube from the torque converter that activates the input pump, in comparison to the old one that I submitted to the rebuild shop. I don't know if there is an external way to know if it is engaging the transmission input gear pump. The trans dip stick shows an over-full high oil level typical as when checking any car without the engine running and a gear not engaged. I'm a seasoned mechanic but first experience with Automatic transmissions/torque converters - I'm stumped. Open to suggestions. _____ I noticed that I first logged onto this site in 2013 but this is only my second time. I've spent lots more time reading and contributing on the JDCrawlers site under this same name. Fortunately the 580 hasn't been much trouble over the last 15 years of ownership.
What is "tractor fluid" ? Should be Case TCH or it's equivalent. Did you clean the oil pan and suction screen ?
Thanks for the reply. Trator fluid is just a hydraulic oil that is also commonly used in tractor transmissions. I don't know who, how or why it got that name, but I've operated several tractors (dozers, excavator) in the northwest logging country for over 15 years, and it is the hydraulic oil one gets from the local farm co-op or tractor supply house - nothing unusual or exotic. Yes, the oil pan and suction screen were removed, cleaned and reinstalled. Thanks you for the suggestions, all help is welcome, and one never knows when or how the answer will pop up. In consultation with my mechanical neighbor, we will check for a clogged transmission vent this morning. Obviously I want to check everything possible (or impossible) before removing the transmission again. Its a mystery because everything seemed to go back together so smoothly and obviously, mechanically speaking.
I sounds like you didn't get your torque converter and shuttle pump drive tangs (for lack of a better word) lined up and the pump is not turning.
If you did not get the torque converter fully installed when you cranked down on the bell housing bolts you broke the ears off the pump. Put a gauge on the transmission and see if you are building any pressure. I suspect you are not and a second attempt at this will be required along with a new pump.
Good news and bad news. The input pump was not being engaged by the torque converter "drive tube" thus not filling the converter. The engagement tangs are 3/8" long and the converter pump drive tube was just slightly over 3/8" too short. I used some washers to space the torque converter 5/16" off of the flex plate, which corrected the oil pumping problem, that is the good news. But now, even though the transmission accepted the correct amount of oil and is at the proper operating level, I am not getting power to the output shaft. Spacing the converter also changes the engagement points for the two spline shafts that go into the converter and take power back into the transmission. So that's the disappointingly bad news. I will have to wait 'til Monday and consult again with the converter rebuilder/transmission expert. Thanks for those suggestions. I was pretty careful with assuring the alignment before each of the installations, visually verifying the positions of the converter and pump gear tangs. For the first "re-mating" I had the engine out and the shuttle suspended so it was easy to gently maneuver and feel that the engagements were proper. Because of some stripped housing threads it is clear to me that the engine/trans had been separated before. The drive tangs on the old oil pump gear had their corner's nicked off, perhaps implying that the first replacement converter drive tube tangs were too short. I didn't observe the defective converter closely before I submitted it to the rebuild shop, but was told that the inside was trashed and might not be rebuildable. Remember the tractor has been driving just fine for at least the last 15 years, and I only separated the units because I was leaking transmission oil into the bell housing. Engine oil was black, tranny oil quite clear and clean, bell housing oil was clear and clean, not black. Apparently the rebuilder does mostly auto torque converters; the actual mechanic employee is a former transmission rebuild shop owner. He mentioned he might have to scrounge up a new converter core, and might have taken measurements from my old converter. The only things I have done to the shuttle transmission is remove and reseal its oil pan, clean the sump screen, and replace the input oil pump with a new one. Its become an interesting, if annoying, troubleshooting problem. As I often do, I keep asking, what changed? I think I've reported everything, but again I keep wondering what I might have overlooked. I even have my mechanic/mechanical engineer neighbor helping with the heavy lifting and watching over my thought processes. This one's got us scratching our heads.
Maybe the scrounged core wasn't exactly the same.
I've fitted scores of converters & shuttles - NEVER needed to "space" / add washers to a flexplate. Either the converter is not correct OR the charge pump is not. I would try to source another converter from a CASE parts supplier. Where was the charge pump purchased? Does it have a part number?
As has been said buy your parts from a case specialist. Screwing around with an automotive trans shop matching stuff up is going to lead to more money and time spent. The torque converter housing drives the pump. Inside the torque converter are a stator and a turbine. The turbine connects to the input shaft of the tranmission. In your case I am guessing the splines were not engaging the turbine. One other variable you might be battling, the transmission may not be original. If there are numbers on it maybe a Case specialist could verify.
Is the flex plate reinforcement ring in place ? Or is it missing, like not in there. If it is in place adding the washers between the flywheel and flex plate would lead me to think that the wrong torque convertor or flywheel is in it. Or both. Adding washers will surely lead to more problems.
Thanks to all for the suggestions. Clearly the the replacement torque converter is short on one end. Structurally I don't like the spacing washers but I was careful with their selection and installation, and for now, they seem to have allowed the convertor to engage the transmission oil pump. The rebuilder tech opined that moving the converter back 5/16" should not adversely affect the engagement of the two splines. The reinforcing ring is in place. It was not thick enough by itself to have affected the engagement into the oil pump. It is possible that the "core" I submitted to this rebuilder was a previous improper replacement. Of course as a troubleshooter, the converter still remains an unfortunate variable but for now it seems to be working well enough to steer me in other directions. I thought maybe the transmission bypass was amiss, so removed the control spool and verified that everything is in order. The solenoid fell off years ago but it has been driving perfectly without it. The output shaft now turns when the engine runs, with no load, but only in one direction, whether the selector is in forward or reverse, but has no power available, I can stop it with my hand. Again I ask what has changed? So the problem is common to both F and R. Now I'm focusing on either insufficient pressure or improper oil. The new pump is physically identical to the old one. I don't know what the rebuilder used for a new converter core, but its outside appearance did not alarm me (notwithstanding the shortness of its pump drive tube). I started to remove the first of two small plugs to initiate pressure testing, but the Allen head stripped out . Back to what changed? The tractor was driving and pulling fine before the teardown. The other variable is the replacement of the old oil with generic "tractor transmission and hydraulic fluid" instead of the Hytran recommended in the service manual. The shuttle transmission has "wet" clutch discs, so the next move is a call to the Case dealer to ask if it is sensitive to the type of oil. Thanks again for your interest and support.
Universal tractor fluid, and just regular AW hydraulic oil will certainly make that transmission pull, it's not good for the wet brakes, and will probably slightly shorten the life of the clutch discs, but many people run that.
Mitch, thank you for the information and encouragement. I'm going to measure the hydraulic pressures per the manual before I remove the trans again and condemn the converter. Of course in the first attempt the Allen head of the access plug stripped. All in a day's work.
It has no solenoid attached? The plunger on the control valve needs to be depressed to have drive........ Perhaps the internal dump valve was stuck before, allowing it to drive without the plunger being depressed - but now it has resumed normal function.
OOh, I thought it was the other way around. I never tried it, but I thought it depressed the plunger to disengage.
Airman! Where were you when I needed you? You are exactly correct, and that plunger operation mode is described in the maintenance manual. It states that the spring within the solenoid plushes in the plunger, (which pushes, through another spring, a second "dump valve" mini-plunger) and when energized, the plunger is sucked back into the solenoid thus opening the bypass and removing pressure from the forward or reverse clutch. So in total there are three springs in the control. As you correctly diagnosed, I was misled because it operated for so many years with the outside plunger fully extended. With the engine running, trans-axle in neutral, bucket and stabilizers down, wheels blocked, shuttle in forward, I crawled beneath, and on a "teenage" sorta whim, I thought 'I wonder what happens if I push on this here thingee?' and the drive shaft spun up to full power immediately. I'm guessing that the shuttle trans oil change dissolved the stuckness of the internal mini-plunger that bypasses drive power. Solenoid coils are expensive and I've never felt the need to bypass the transmission (I can still manually shift it out of F or R for the same effect) so I just modified my large nut so it holds the plunger in and actuator lever on. (The nut is 1-1/4x7) Along the way I did manage to make a pressure check, after discovering that an appropriately sized Torx bit makes a good "stripped Allen socket" removal tool. While I had the engine out I pressure washed 40 years of oil soaked dirt off of the frame, hoses, pipes and engine, and painted the engine the closest color I could find to "CASE Tan" that was heat resistant. Thanks again to Mitch504 - the shuttle trans works just fine with the generic tractor fluid. And finally, thanks again to all for the interest and suggestions.