powershift case 970 question

I noticed that the sungear is hanging down on the input shaft, and has a lot of slop up and down , and between the sintered plate and the snaprings.

what i found when i split the tractor was that the C4 sungear was almost wore trough by the input shaft, and had destroyed the planetary gears in the proces.

But it seems like with new parts installed that the stage for failure again is allready been set.

It seems to me, when C4 clutch is pressured up it will lock the clutch plates in out of center, and make the sungear wobble around its axis on the front . the gear is held more or less centered by the 3 satelite gears of the planetary in the rear, but under a angle to them.

Does anyone has an answer to this??

Thanks up front

Although the wear on the ID of your sungear seems to contradict this opinion!

I can see the self aligning happening if you could feather the clutch, but that is just about imposible with these case's

That logic is only this guys opinion of the Case Powershift operation. I certainly welcome further dialog and/or confirmation of this supposition.

Although, all this talk doesn't explain your problem of C4 sungear wearing on the input shaft??
Come-on you Case mechanics out there... comments please... we all want to learn !!

What i did to correct this is as follows.
I took the front snapring of, then i cut out a big washer out of a steel plate 3/16 thick,and turned the ID to fit the snapring groove and machined a step in there to take up the play between the groove and the plate. The OD I turned down only far enough to be able to use the six existing holes in the clutch plate.
then i cut the washer in half,put it on the gear like you would a snapring, drilled the holes and tapped tread, and bolted the whole thing solid.
I turned the boltheads down to make enough clearance between the 2 clutchplates.

Now with everything together the sungear is almost centered, and I don't think will cause no problems no more. I hope

Whadda ye think.

Simon

I do believe the planetary spins whenever the engine is running. Although backward from engine direction when C4 is engaged in reverse or the clutch pedal is depressed.
Think about it... the input shaft is directly splined to the flywheel through the torque limit clutch system and the primary sungear (rearmost) is part of the input shaft. The primary sungear is always engaged to it's set of 3 planet gears. So the planetary hub also spins. This is the very action that I believe causes the C4 sungear to self-center around it's planet gearset. I guess I'm saying that the self-centering action is providing a bearing-like effect supporting the sungear from "flopping around". Just my opinion, from studying the Service Manual pictorials.

As to my opinion of what you did to resolve the problem >>>
It's worrisome to me to add a new part that the Case folks didn't engineer into the initial design. One thing to consider... not vary many powershift transmissions apparently exhibit your problem or it would soon be very much public knowledge, especially thru the Forum. So, at this point, I'll refrain from comment until I can sit down in front of the Case Service Manual and study what you've described you've incorporated. It's 2:30 AM, so stay tuned for a follow-up reply, hopefully tomorrow... after fireworks.

First learned point >> I believe we both miss-named the clutch and sungear that your having the problem with. The forward-most clutch that locks your self-destructing secondary sungear (or reaction sun gear, as the manual calls it). Is actually the C1 not the C4. Second point: The C4 clutch does, when engaged, create reverse but only the planet carrier spins backward not the entire planetary. So my point about the subject sun gear self-centering when the system is spinning backwards to create reverse gear may be even more plausible, since the C1 is not engaged at this time.

But more to your issue > further learned is that the reaction sun gear bearing/centering method is quite different between a Powershift unit with PTO and without PTO. So does your 970 have PTO? I assume yes, as most tractors of that size/HP are so equipped.

The difference in relation to the reaction sun gear support is:
With PTO > The reaction sun gear is riveted to the forward-most sintered metal clutch plate in the C1 clutch assembly. This creates an assembly that is centered concentric with the clutch hub and therefore the hollow input shaft. The PTO & hydraulic pump drive shaft pass through the input shaft.
Without PTO > The reaction sun gear is centered concentric & supported by the solid input shaft, which also drives the hydraulic pump. This bearing method is provided by a part called the "C1 clutch support bushing". The ID of this bushing is splined onto the input shaft. It's OD is the surface which mates with the ID of the reaction sun gear. There is also a compression spring between this bushing and the primary sun gear which pushes the two sun gears apart and against snap-rings on the input shaft.

All this was quite enlightening to me. But bear-in-mind that this info is from the 4x4 Case Service Manuals. Seems the 2470, 2670 & 2870 are all the same in respect to the reaction sun gear. The Service Manuals are an excellent written and helpful book when it comes to these complicated machines. At least to this dummy! Do you have a Service Manual for the 970?

Don't exactly know how this information may relate to your added-part modification on the 970. I would appreciate feedback as to your considerations and how you may proceed to fix the problem.

Good Luck, Jim B.

yes i have a service manual,but it does not mention any of the things you talk about. and yes the tractor has PTO.
this tractor is secondhand, and the powershift has been apart before, i can tell cause of mismatched bolts inside and lots of rtv sealant instead of a gasket between eng and tranny.altough it apears things where put together correctly. i do have extensive mechanical experience, but case is new to me.

I understood that C4 clutch was reverse,but I could be wrong[i did not realy study the manual that close].If the pto version requares that the sintered clutchplate be rivetted to the sungear,wich was not the case with the failed parts, than my observation as to how to fix the problem seems correct. as i made the sintered plate more rigid to the sungear.and keeps the sungear better centered because the plate leans at the top against the cover, and the sungear can't slide down with the play provided by stock parts.I took out about 90% of the play. so there is still some play, a couple of thou.

Maby the new used parts are incorrect for this aplication, but i thought the failed parts where the correct ones to start with, and neither the dealer or wrecker informed me that there where different options,but the manual shows the same parts i have.

What i did see and baffled me a bit, is that the input shaft OD is roughly machined and the sungear ID looks like it was made to ride on a bearing or bushing. That was wy i posted the question[ what is supposed to keep the sungear centered]

Anyway i will study my manual tomorrow, and get back to you, its time to do some shuteye.

Simon

C1, the fried clutch,together with C2 operates 1st [low]
C1,together with C3 operate 2nd [intermediate].
C2 and C3 make 3rd [high] work.
C4 is locked by itself only if the inching pedal is depressed.
All clutches not locked in recieve lube oil pressure,. Wich lead me to the conclusion that the C1 clutch sungear could be locked in out of center.
I can't see any other way that these parts could fail.

Having said all that,leads to another question.
If C1 has nothing to do with reverse, how come reverse was absent,and all other gears still worked. Do I have to contact Fox Mulder[exfiles].
Now I am more confused than ever.

Anyway I buttoned the tractor up, and took it for a spin. All shifts work flawlesly including reverse. Only when in neutral with inching pedal depressed the tranny sounds somewhat noisy,but not always, could that be some residual air in the system
one other thing, of the 8 parts yards I contacted only 1 had the sungear , sintered and steel plate, and clutch cover for the C1 clutch.
Makes me think the failures of that clutch could be more wide spread than you think.
also, the new used sungear had also evidence of dragging on the front ID, but little.
Hope you can make head or tails outta this?

Simon

In regard to the tranny lub circuit... the 4x4 manual indicates that the lub oil supply comes directly from the oil cooler which is returning oil from the steering circuit. This is totally separate from the Powershift hydraulic control circuit. In fact it's even a different portion of the triple pump. The exception is: the somewhat external lub-tube that squirts directly onto the C1 clutch front face. That's the vertical tube coming thru the bottom of the flywheel housing. That oil supply comes directly from the pressurized filter housing, which make me believe it may be an after-thought to resolve an over-heating problem ??
So, the lub oil supply is independent to clutch application(s) and is always flowing, except when the clutch (inching) pedal is depressed. The reason flow stops during clutch pedal depression is the lub oil circuit also applies the reverse lockout valve and that pressure is dumped-to-the-sump by the inching spool valve so as to release the reverse lockout.

Sorry, I don't have a clue why the C1 failure affected reverse?? Apparently, even though your C1 was self-destructing it still functioned... Wow !

As I mentioned earlier... I believe the whining noise heard when the inching pedal is depressed is because the C4 clutch applies, locks the planetary hub causing the planet carrier to spin backwards and creates reverse. Of course, to fully engage reverse the Powershift lever must be moved to reverse and the inching pedal released which engages the back-spinning planet carrier to the output shaft when the C2 clutch engages.

If you didn't know...CaseIH has very good Websites where the Parts Manuals may be accessed. There are separate sites for Agriculture machines, like your 970, and Construction equipment. For Ag the link is:>Link
For>Link Construction it's:>Link
The opening screen for these sites is mostly advertisement for CaseIH... but just click-on the "search for parts here" words and a separate screen will open. Then type-in the model of interest (970) in the search box. Then a list of several 970's will be displayed. Find the: 970 Comfort King Tractor which includes your serial number and click-on it. A list of pages from the Parts Manual will generate. Find the page for the Powershift with your serial number, click-on it. Then scrool down to thw C1-C4 page, click it. A list of parts with numbers will generate at the bottom of the screen and the pictorial will generate at the upper right portion of the screen. A picture is always worth more than words.

I brought-up the C1-C4 page and it shows the C1 sun gear attached to the sintered metal clutch plate as an ASSEMBLY. Just like the 4x4 tractors.
Sounds like your repair may be similar to a design change Case made sometime during production ??
Hope this helps you.

Glad to hear the machine now functions OK.
Good Job, thanx for the dialog.
Jim B.

PS, If you have trouble accessing the Case IH Parts Manual Website.... send me an Email (so I can privately get your address) and I will reply with copy & pasted attachments of the subject pictorial.

and it looks like I might have done that here to, but time will tell. Altough a bushing or bearing between that sungear and the input shaft would have been the best solution, but could not be acomplished.

The service department at the dealership was less than helpfull as no one there knows dickall about them. Most mechanics these day's are replacers instead of fixers.

Thanks for the info on the case website, i"ll look into that.

Have a very good day

Simon