970 Transmission Issues

[GW Thwaite]

My 970 Case mid 70"s model is slipping out of gear.

-I found a small leak in a line, replaced

-I changed the trans. oil and filters

-when I start up tractor it works well for a few minutes, then it will not engage into the selected gear, but if I change gears, it works, both forward and reverse.

-Having exhausted all local resources it was suggested to try this site.

Any suggestions?

GW

 

[cshess]

Lot experts on here but you need to give more info. What gear? Is it regular transmission sliping out or is power shift not shifting corectly.If it is regular 4 speed gear trans perhaps shifter is not fully moving forks an cables just need adjusted. Place to start any way. Do give ore info an folks will help on here.

 

[cshess]

Lot experts on here but you need to give more info. What gear? Is it regular transmission sliping out or is power shift not shifting corectly.If it is regular 4 speed gear trans perhaps shifter is not fully moving forks an cables just need adjusted. Place to start any way. Do give ore info an folks will help on here.

 

[GW Thwaite]

My observations:

-it pulls well in 2&3 gears in second range, but not first and third ranges.

-I first noticed it when I took it out on the road and put it in road gear and I had problems with it shifting into 2 & 3 ranges.

-I also notice the PTO does not stop turning, even though it is in the stop position.

I have stripped the tractor down to expose the top of the tranny, I see a couple of adjustment screws on the top.

GW

 

[Brokengun]

I don’t think there is an adjustment screw that’s going to solve your problem.

Please before you do anything else run the pressures on the power-shift. There are plugs in the PS valve on the side of the tractor that allows you to attach a pressure gauge you need at least 2 gauges that can read 300-400 psi with hoses.

Get a book on the tractor if you don’t already have one, to help you diagnose the problem

I use a bank of 5 gauges with 6-7 ft long hoses so I can set in the tractor and watch as I do the pressure test for the power-shift.

P.S. you can always make up a hose using the hose off of a grease gun but it will require a helper to read the gauges.

 

[mEl]

(quoted from post at 07:35:58 05/08/11) I don’t think there is an adjustment screw that’s going to solve your problem.

Please before you do anything else run the pressures on the power-shift. There are plugs in the PS valve on the side of the tractor that allows you to attach a pressure gauge you need at least 2 gauges that can read 300-400 psi with hoses.

Get a book on the tractor if you don’t already have one, to help you diagnose the problem

I use a bank of 5 gauges with 6-7 ft long hoses so I can set in the tractor and watch as I do the pressure test for the power-shift.

P.S. you can always make up a hose using the hose off of a grease gun but it will require a helper to read the gauges.

Brokengun, The 970 valve is under the floorboard on the platform. The gage manifold sure beats removing gages and reinstalling them each time a different set of clutches is tested. You are correct, any info given without pressure readings is just speculation. mEl

 

[GW Thwaite]

I appreciate your input.

Can I use the tractor as is?

I have removed the floor cover and power washed the top of the tranny.

I found two lines @ the front of the tractor with test fittings, are these the correct lines to check for pressures?

GW

 

[mEl]

No, there are plugs in the powershift valve cover marked C1-C2-C3-C4. Those are the clutch pressure test ports and by checking all them in their proper sequence you can diagnose the hydraulic portion of the powershift. You should really have a service manual. I have put all the test info up here many times and you could go back and check the archives and retrieve it. I am a hunt and peck guy as I never had typing and post with difficulty. In a nutshell, C1-C2 make 1st Powershift speed, C1-C3 make 2nd and C2-C3 make 3rd. C2-C4 make reverse. so these should be checked as pairs. A dealer would have a multigage setup to install in all ports at once. If you intend to do this testing if you do not have a proper square socket to remove those plugs get one first as once they are rounded off by adjustables or vice grips they become almost impossible to get out. mEl

 

[GW Thwaite]

Progress is being made:

-I obtained a shop manual and beginning to understand the situation.

-I did search the archives only to find a different scenario situation.

-Having spoken with the local Dealership's service mgr., he has told me the problem may correct itself once the clean transmission oil is warmed up and flowing through all of the lines.

-reverse is working well along with middle range on the power shift.

-in second gear ALL Power Shift Ranges work well.

-I am keeping my fingers and toes crossed hoping the lines/valves will flush out.

-I am thinking since the tractor sat all winter, the fibers collected and has caused this situation.

GW