JD 950 SCV Valve

   / JD 950 SCV Valve #1  

ChoPChoP

Member
Joined
Oct 17, 2010
Messages
27
Location
Rhode Island
Tractor
John Deere 950
Anyone know what would cause this on my JD950? When I first start it I have to push really hard on the bucket tip lever to get it to move. It seems fine if I keep using it but if I run around for awhile, without using the FEL, it will do the same thing and I will have to push hard to get it working. I've rebuilt the valve and the pistons and the FEL has worked fine for the last year. This showed up after I had been dragging backwards with a rachet rake on my driveway.

Thanks,
 
   / JD 950 SCV Valve #2  
I believe I would put a hyd gage in a tee at the IN port of the loader valve, and observe the pressure required to operate the cyl..
 
   / JD 950 SCV Valve
  • Thread Starter
#3  
I believe I would put a hyd gage in a tee at the IN port of the loader valve, and observe the pressure required to operate the cyl..

J_J thanks for the the advice, I ordered the pasts to make one. Just out of curiosity I switched the in and out hoses, so the bucket curl & tip was reversed, just to see what would happen. Same thing, I had to push on the handle to get it to move after it sat for a while. I then switched the boom hoses with the bucket hoses and it still did it so I am 90% sure it is something wrong with the valve. It is also pushing HO out the top of the valve where the breather cap is. Whaddya think, valve replacement?:confused:

Thanks,
 
   / JD 950 SCV Valve #4  
Have you inspected the load checks springs and seat for damage, or debris.

You really can't rebuild a hyd valve as the spools are a precision fit and when they are worn, that is it.

You can replace some o-rings on the outer part of the spool where the spool exits the valve block.

Is the spool binding? Sometimes over tightening will warp the valve and cause problems.

As fluid warms up, it mover around better.
 
   / JD 950 SCV Valve
  • Thread Starter
#5  
Have you inspected the load checks springs and seat for damage, or debris.

You really can't rebuild a hyd valve as the spools are a precision fit and when they are worn, that is it.

You can replace some o-rings on the outer part of the spool where the spool exits the valve block.

Is the spool binding? Sometimes over tightening will warp the valve and cause problems.

As fluid warms up, it mover around better.

J-J I will pull the valve off tomorrow and take another look at it. Forecast says rain anyway so not tractor fun.

The spools are not binding and work great after the initial push to get the tip lever going. Nor were they not sloppy when I rebuilt the valve and was careful to keep track of where they went. Rebuild as in new O-Rings Springs and C Clips.

Found a guy on Ebay selling the JD replacements for 1/2 of what JD sells them for. I'm pretty well convinced it's the valve so I may just go for it.
 
   / JD 950 SCV Valve
  • Thread Starter
#7  
Had some rain this morning so I pulled the valve and took apart the top end of the bucket spool. The O-Ring was gone or half of it anyway. It must have blown apart when I was back dragging with the ratchet rake on my driveway. Threw in a new one and used the FEL all afternoon without a problem and no leaks so I guess that was it. I just replaced the O-rings last fall so I didn't think that could be the problem but like my wife says, I am often wrong with my assumptions. :)

Nice valve though, I would really prefer to have a joystick and the quick dump would really be nice. Only problem is all my lines are steel tubing so that would require some major plumbing changes.

Thanks J_J, you are always so helpful on here.
 
 
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