John Deere 2955 Hydraulic Issues Help!

[mkt]

Tx Jim, Thanks for the information. I'll see if I can find the 28-31 hyd relief valve and remove it, clean it etc. From the drawing it appears it is near the screen ( to the right) of the screen. Thank you! Mark

 

[Kyle_in_Tex]

So does it still work ok when cold, but deteriorate as it gets hot?

 

[Tx Jim]

JD closed center hyd systems are so much fun to diagnose that they will make one's hair turn gray or fall out. After 13 yrs serving as a JD dealer service manager diagnosing CC hyd problems I'm a shining example.:laughing:

 

[mkt]

Here is the latest: I called a John Deere dealer in SC and talked with a service manger. I told him what all was going on and he said it was probably brakes but suggested I drain all the oil, put in new filters and see what happens. I drained all the oil ( I had close to 15 gallons in it, milky looking fluid. I put in a new hyd filter ( NAPA) and 9 gallons of Tractor Supply oil. I did pull out the "bypass valve right above the hyd filter and it has one very small piece of debris. I pushed the valve against the spring it worked fine and was tight. I put it back in. I also checked the screen and it was clean.. I started the tractor and she started working with some jerking on the 3 point hitch and lifted the harrow actuator slowly. He said try and screw in the "destroker valve" I did so and back it back out. He said if it works, just run it, so I did... I was able to plow my dove field about 2.5 acres. toward the end of plowing it twice it I started using the brakes to help turn. Then I lost brakes and sterling became jerky and hard with lower RPM. I was going to plow another filed (small area) but I took the tractor back to the shed.. I'm going to let it sit over night and see what the fluid level is tomorrow morning.
The tractor only has one valve that is used to lift the harrow actuator ( cylinder). Thanks everyone..

 

[Kyle_in_Tex]

Here is the latest: I called a John Deere dealer in SC and talked with a service manger. I told him what all was going on and he said it was probably brakes but suggested I drain all the oil, put in new filters and see what happens. I drained all the oil ( I had close to 15 gallons in it, milky looking fluid. I put in a new hyd filter ( NAPA) and 9 gallons of Tractor Supply oil. I did pull out the "bypass valve right above the hyd filter and it has one very small piece of debris. I pushed the valve against the spring it worked fine and was tight. I put it back in. I also checked the screen and it was clean.. I started the tractor and she started working with some jerking on the 3 point hitch and lifted the harrow actuator slowly. He said try and screw in the "destroker valve" I did so and back it back out. He said if it works, just run it, so I did... I was able to plow my dove field about 2.5 acres. toward the end of plowing it twice it I started using the brakes to help turn. Then I lost brakes and sterling became jerky and hard with lower RPM. I was going to plow another filed (small area) but I took the tractor back to the shed.. I'm going to let it sit over night and see what the fluid level is tomorrow morning.
The tractor only has one valve that is used to lift the harrow actuator ( cylinder). Thanks everyone..

When it's hot is the best time to check the transmission charge pump flow.

 

[Tx Jim]

With hyd oil at operating temp,3pt raised,engine running look in open hyd filler hole behind seat for moving/spraying oil. If moving oil is seen this indicates an internal leak which will severely affect hyd operation.

I seriously doubt if screen had no brake material on it that brakes are causing your tractors hyd problems.

 

[Kyle_in_Tex]

With hyd oil at operating temp,3pt raised,engine running look in open hyd filler hole behind seat for moving/spraying oil. If moving oil is seen this indicates an internal leak which will severely affect hyd operation.

I seriously doubt if screen had no brake material on it that brakes are causing your tractors hyd problems.

Good info.

 

[gary49]

OP's second post says the screen was full of debris when he first took it out. I believe he also mentioned milky hydraulic oil. Water in the oil can cause lining to come off brake discs. Our 2155 had multiple issues for this reason. Seems likely brake deterioration is what has caused his problem.

 

[Tx Jim]

I agree on milky fluid isn't a good thing BUT milky fluid can cause debris on screen without brake pad deterioration. IMHO & experience amount of brake pad deterioration will be determined by how long moisture is in oil in trans case. If brake pads have deteriorated then metal fines will begin to show up in bottom of trans case & if continued use of tractor fines will end up throughout hyd system. I've spent unknown hrs diagnosing JD CC hyd system problems due to the fact I served as a JD dealer service manager for 13 yrs of the 21 yrs at dealership during the hey day of closed center hyds on JD tractors. It would be very difficult for dealer service manager in SC to accurately diagnose OP's tractor as brake problem over the phone just the same as it's difficult to accurately diagnose hyd problem looking at computer monitor.

 

[mkt]

I checked the fluid level this morning at it wasn稚 even on the dip stick. (No noticeable leaks under tractor) I bought more fluid and I will fill it to correct level. I will also remove the oil cap and look for any spraying oil inside. If it runs I will plow some more and see how it does. One question is if it does have an internal leak where is the fluid going? Thank to all of you!