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I have a 1976 Case 2670 that the hydraulic remotes have been getting slow and the last time I used it plowing the tractor nearly stalled out. I was in 2nd or 3rd powershift and stepped on the clutch pedal and now I barely have any hydraulic pressure in powershift 1 and 2 and also N. But hydraulics work perfect in 3rd and when I press the clutch pedal. Does anyone have any ideas or experience the same issue? I am thinking there is something internal in the transmission like a seal or a leaking supply line or something by passing with in. Any advise would be appreciated. Thanks.
 

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Just went through a similar experience with a 4694. We had a gasket leaking between the power shift valve block and the transmission and a powershift valve or two not working correctly. The gasket was leaking internally from one passage to another. This is the block under the floor of the cab.
 

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Just went through a similar experience with a 4694. We had a gasket leaking between the power shift valve block and the transmission and a powershift valve or two not working correctly. The gasket was leaking internally from one passage to another. This is the block under the floor of the cab.
Thank you very much!
 

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check your suction screen on hydraulic intake. I think its a hyd problem not a RPS problem.Is any shift slipping
 

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check your suction screen on hydraulic intake. I think its a hyd problem not a RPS problem.Is any shift slipping
No shift slipping, pulls strong in every gear and speed. But all hydros function proper while in power shift 3 “direct drive”. And also with inching pedal fully pressed.
Very little hyd pressure to remotes and 3 point hitch while clutch pedal is in home position and power shift speed selector is in 1st and 2nd.
I’m not opposed to the screen being plugged. But I find it strange that the screen would suddenly become unplugged by stepping on the inching pedal or placing the power shift selector in 3.
As I said the hyds all function perfectly while pedal is pushed or tractor is moving in powershift 3.
 

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there is a flow divider on the side of frame that gives priority the flow to RPS maybe that spool stuck. The RPS does not require a lot of oil to run.The only other thing could be the bearing in the carrier A76468 is gone and carrier has that much leakage. Remove the valve body from trans cover and at the back in the middle of the housing there is three holes , put air to them you should not have much leakage
 

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there is a flow divider on the side of frame that gives priority the flow to RPS maybe that spool stuck. The RPS does not require a lot of oil to run.The only other thing could be the bearing in the carrier A76468 is gone and carrier has that much leakage. Remove the valve body from trans cover and at the back in the middle of the housing there is three holes , put air to them you should not have much leakage
Thank you very much! That gives me a few things to start on when I get a bit of time to tear into her.
I greatly appreciate all the information.
 

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Thank you very much! That gives me a few things to start on when I get a bit of time to tear into her.
I greatly appreciate all the information.
Oh and I forgot until looking at it for a moment today it has a very noticeable trans hyd leak coming from the first section of the transmission housing that bolts to the bell housing.
 

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Have you checked the hydraulic pressures? There is a procedure for doing so in the service manual that will tell you a lot more about what is going on.

I suspect that some of the seals are gone in one of the RPS 34 clutches, only because I have the exact same problem with my 2870. (Very low hydraulic flow in one of the power shift ranges. When I checked pressures sure enough one is low, C3 I think, forget just now) It is waiting for a space to open up in our shop to rebuild the RPS 34. It is highly recommended to NOT run the tractor for fear of tearing up clutch linings that may not be getting enough oil to fully engage or disengage.

I recently rebuilt the power shift in our MF 2705. When I disassembled the power shift unit I could not believe how badly some of the (40 year old) orings and seals had deteriorated. They were no longer rubber, they had turned to plastic and cracked all to pieces.

I'm expecting to find the same thing in the 2870, and wouldn't be surprised if you find something similar in your 2670.
 

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Have you checked the hydraulic pressures? There is a procedure for doing so in the service manual that will tell you a lot more about what is going on.

I suspect that some of the seals are gone in one of the RPS 34 clutches, only because I have the exact same problem with my 2870. (Very low hydraulic flow in one of the power shift ranges. When I checked pressures sure enough one is low, C3 I think, forget just now) It is waiting for a space to open up in our shop to rebuild the RPS 34. It is highly recommended to NOT run the tractor for fear of tearing up clutch linings that may not be getting enough oil to fully engage or disengage.

I recently rebuilt the power shift in our MF 2705. When I disassembled the power shift unit I could not believe how badly some of the (40 year old) orings and seals had deteriorated. They were no longer rubber, they had turned to plastic and cracked all to pieces.

I'm expecting to find the same thing in the 2870, and wouldn't be surprised if you find something similar in your 2670.
Thank you for the information. I have a feeling that is a big part of what is going on. I too am waiting to get it into the shop when time permits, just looking for ideas before I start working on it. I have a service manual and have been studying it. I’ll have to get some gauges and small lines for testing.
But from what I’ve seen in the hydraulic schematics for RPS there is “one” common denominator with RPS 1,2,and inching pedal “not” fully depressed. And that common is C1 clutch.
while RPS is in “3” and also while clutch pedal is “Fully” depressed there is “no” pressurized transmission clutch oil directed to C1.
But C1 has hyd pressure in every other RPS position. And C1 is the first clutch pack in the trans housing which makes me think that might be why there is oil leaking from the first trans housing.
sure would be nice if it was an external problem. Time and testing will tell. “I hope”!
 

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I have a 1976 Case 2670 that the hydraulic remotes have been getting slow and the last time I used it plowing the tractor nearly stalled out. I was in 2nd or 3rd powershift and stepped on the clutch pedal and now I barely have any hydraulic pressure in powershift 1 and 2 and also N. But hydraulics work perfect in 3rd and when I press the clutch pedal. Does anyone have any ideas or experience the same issue? I am thinking there is something internal in the transmission like a seal or a leaking supply line or something by passing with in. Any advise would be appreciated. Thanks.
Let us know when you find the problem. I have a 1976 1070 Agri King with a similar problem. 1st power shift gear is slow to activate and 2nd and 3rd work better. Also hydraulics will only operate when clutch pedal is pushed down.
 
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