# JD 950 Hyd Issue



## Rick McW (Dec 3, 2019)

Hi all, I'm new to site, have a question about hydraulics, when I operate FEL the 3PTH drops, didn't do when first purchased tractor used. Also when shutoff tractor 3PTH drops.
not sure if pump problem or bypassing somewhere, any help would be appreciated!


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## Fedup (Feb 25, 2014)

Many hydraulic issues can be caused by more than one problem, and this one is no exception. However in MOST cases the problem described is caused by faulty piston seals in the internal three point lift cylinder. They don't generally fail all at once so it's not unusual that the problem has come on and gradually gotten worse over time.


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## Rick McW (Dec 3, 2019)

Fedup said:


> Many hydraulic issues can be caused by more than one problem, and this one is no exception. However in MOST cases the problem described is caused by faulty piston seals in the internal three point lift cylinder. They don't generally fail all at once so it's not unusual that the problem has come on and gradually gotten worse over time.


I disassembled 3pth assembly earlier and replaced seals but noticed bore was slightly scored, so that could causes problem? anyway to repair bore? Hone? Thanks for reply


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## Fedup (Feb 25, 2014)

John Deere parts website doesn't show the cylinder as a replaceable part. Leads me to believe it's cast and machined into the lift housing. Not a good sign in that regard. 

Honing MIGHT help, but in my opinion scores and scratches will equal leaks no matter what. It appears that if you remove the top link bracket/rear cover from the lift housing you should be able to see the back of the piston, the rod and all that. I would think at that point you can run the engine, raise the lift arms, apply some load to the arms and observe what's happening in there leak wise. You can then determine if that's part of your problem or not and think about where to go next.


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## Rick McW (Dec 3, 2019)

Fedup said:


> John Deere parts website doesn't show the cylinder as a replaceable part. Leads me to believe it's cast and machined into the lift housing. Not a good sign in that regard.
> 
> Honing MIGHT help, but in my opinion scores and scratches will equal leaks no matter what. It appears that if you remove the top link bracket/rear cover from the lift housing you should be able to see the back of the piston, the rod and all that. I would think at that point you can run the engine, raise the lift arms, apply some load to the arms and observe what's happening in there leak wise. You can then determine if that's part of your problem or not and think about where to go next.


so since piston is leaking by , you are thinking when I operate front end loader its enough pressure loss to cause 3pth to drop?


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## Fedup (Feb 25, 2014)

Definite possibility


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## dragonslayr (Sep 17, 2019)

... ... soooo Rick McW... did you do anything to resolve your problem with the bleed off?


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## deerhide (Oct 20, 2016)

RickMcW;
Has your fel lost any lifting power?


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## bmaverick (Feb 20, 2014)

Rick McW said:


> I disassembled 3pth assembly earlier and replaced seals but noticed bore was slightly scored, so that could causes problem? anyway to repair bore? Hone? Thanks for reply


Your John Deere is really a green painted Yanmar. With that said, should JD not have the parts, then contact a Yanmar parts supplier like Hoye or Fredricks. There are rebuild kits and parts available.

https://www.fredricksoutdoor.com/john-deere

https://www.hoyetractor.com/CTGY/JD950.htm
Hyd valve
https://www.hoyetractor.com/PROD/CH19700.htm 
Hyd pump 11cc
https://www.hoyetractor.com/PROD/CH13990.htm 
Hyd pump 9cc
https://www.hoyetractor.com/PROD/CH11272.htm 

Also, 3 of the JD 850/950/1050 manuals are here on this site under the MANUALS > Tractor > Compact Tractor. look at the top menu bar and click there.   Green or Red or Yellow it's still a Yanmar.


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## dragonslayr (Sep 17, 2019)

yup; an mines purple ,,,,,,,,,,,,,,,, Where ya at Rick?


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