2670 c2 clutch issue.

[masonvn]

So I have been playing with my power shift some more. I've narrowed it down to something has to be wrong with the c2 clutch. I will check the pressure tomorrow, but my question is, is it possible for the clutch piston to be stuck in the carrier and not engage the clutches? I put in all used clutch pistons without disassembling them from the carriers. I know that probably wasn't the best idea, as I should have resealed them all, but the guy who owned the donor tractor said it shifted fine 2 yrs ago when they took the engine out. It pulls good in ps 2 and goes into the other gears but you put your foot on the brake and it stops moving. Based on this, the c2 clutch is the only one in common with reverse, 1st and 3rd. I'm 99% sure I was able to count to 6 when putting in plates, and I felt good about the bellville springs staying in place as well during reassembly. I haven't messed with the control valve at all, I assume everything should be still functioning fine with it, but it has been sitting for almost a year. It took me a while to get up the nerve to work on it. LOL Anyways, I was just wondering if anyone else has ever put one back together and had a similar problem. Thanks .

 

[John Saeli]

Have you looked at the Torque Limiter?

 

[masonvn]

(quoted from post at 10:39:26 03/05/19) Have you looked at the Torque Limiter?

I have not since putting the engine back in, it looked like new and I'm assuming it is still fine because it will pull fine in 2nd power shift. Its just reverse, 1st and 3rd that are weak which if I'm right all have the c2 clutch in common.

 

[1370rod]

It sure sounds like C-2 is the problem, I would check pressure on C-2 for the heck of it before tearing it down. If you have the CASE service manual it will explain the
procedure and how to make a isolation plug to determine if a leak is in the trans or control valve in the case oil pressure is low. Rod.

 

[Jeremy McNary]

I have never been around the 4wd cases but I assume that the powershift is similar to the 2wd models, does it have the three tubes that go
from the valve to the oil distributor that are held in with orings on each end? If so take a look there first before a full tear down, I have
had two separate instances of one of those tubes working its way out and it allows the oil to bypass and not engage the clutch for that
particular tube. First time it happened in a 2290 and it was the tube that ran the c2 circuit and I had all the same issues you describe.

 

[masonvn]

Thanks guys, I am for sure going to check the pressure. I do have the case shop manual. It's just been too cold here to fool with it as my shop isn't heated. I'll let you know what I come up with. As for the oil supply tube, I'd like to think there is no problems with it or the control valve in general, but anything is possible. You have to keep in mind, I've been working on this for a year, my original problem being a bust planetary drum and bearing gone from a planet gear. All clutches functioned fine, it just made a terrible noise when you pushed down the clutch and put it in reverse. That being said, I did a complete swap from a used tractor that was said to be shifting good when parked roughly 2 years ago. I inspected all the clutch plates but didn't remove the pistons from their carriers. Now, I'm 99% convinced that c2 piston is stuck in the carrier. I'm guessing the pressure should check fine if the piston is stuck? Is it even possible for the piston to be stuck to the point 190psi won't push it out? I'm just trying to cover every possible scenario.

 

[cnh]

Perhaps the jumper tube is split? I seem to remember seeing some of the black plastic jumper tubes that would develop a split along their length and thus cause the oil to not get to the clutch needed. But my memory cant remeber if this was on the RPS transmission or a different one. 2470 I believe used 5 discs in C2, 2670 used 6 discs, I think.

 

[cnh]

What about if the piston carrier for C2/C3 was not timed correctly when installed, or if the o-rings (I thought they were a square cut o-ring?) were damaged/missing, or the carrier installed upside down? Could this cause a similar issue? Just throwing ideas out there to ponder, someone who had one of these apart lately may be able to lead you in a better direction.

 

[masonvn]

(quoted from post at 00:29:55 03/07/19) What about if the piston carrier for C2/C3 was not timed correctly when installed, or if the o-rings (I thought they were a square cut o-ring?) were damaged/missing, or the carrier installed upside down? Could this cause a similar issue? Just throwing ideas out there to ponder, someone who had one of these apart lately may be able to lead you in a better direction.

i've been racking my brain on this subject, I paid close attention to the timing marks when putting it together. I am pretty confident the c3 is working right, so I think if the timing was off, neither of them would work. Perhaps someone that knows way more than me could correct me if I'm wrong. I inspected the o-rings and they "looked" fine. Who knows. I just hope if the pressure test doesn't give me a clue that I can find the problem when I tear it back down.

 

[masonvn]

Just to update this a bit, I checked the pressure on the c2 tonight and I can get 175 psi and the tractor still will barley pull. What I did find to be odd was to get the pressure up that high, I had to pull up on the inching pedal. Otherwise, it stayed around 125. I'm guessing the pedal must be out of adjustment or the linkage is sticky. I suppose the only thing left to do is tear it back apart since the I'm able to get 175 psi on the c2 and it still doesn't pull any better?

 

[masonvn]

(quoted from post at 20:03:38 03/07/19) Just to update this a bit, I checked the pressure on the c2 tonight and I can get 175 psi and the tractor still will barley pull. What I did find to be odd was to get the pressure up that high, I had to pull up on the inching pedal. Otherwise, it stayed around 125. I'm guessing the pedal must be out of adjustment or the linkage is sticky. I suppose the only thing left to do is tear it back apart since the I'm able to get 175 psi on the c2 and it still doesn't pull any better?

So today, I pulled everything back apart. Everything looked to be just as it should. No bellville springs were out of place and all clutch disks and steel plates looked good. I didn't double check the timing marks coming apart. I was pretty confident the c3 was working fine, is it possible to have the timing off and have c3 but not c2? Just wondering as I'm at a loss here.