jd 6400 hydraulics

stoneridge · May 29, 2016

other than linkage what would cause a rear spool on a 6400 to quit working?
Had one quit a while back and have been getting along with only one. Now the pump seems to surge when warm and tractor idling. Spool still working but would like any input on what to look for before i take apart
was told by dealership to swap the spools to see if it helped or if anything was broken or obviously wrong inside.

Bob · May 29, 2016

NOT sure what you have going on, but the coupler bodies threaded into the valve can fail internally making it seem like the actual SCV is not working, when actually it's just a coupler body issue.

If it is NOT simply a coupler body I suggest NOT tearing into it without having a factory service manual at hand, and followung the troubleshooting procedures it suggests.

Also, be aware that there are "valve discs" or "dime valves" between each section of the valvestack that can get lost, get out of place, or get where they can do damage.

stoneridge · May 30, 2016

was told it could be one of the "dime"valves that might be causing a problem.
I always have the exploded view of parts from deere website to guide me through the process but don't have access to shop manuals. can I find them online? .
I'll look into the coupler idea before taking stacks apart, thanks for that. I have had problems with the originals in the past and have aftermarket couplers on the stack that works.

is it possible that the casting of stacks could be worn after 10k hrs of use?

Bob · Jun 1, 2016

If it has been working in the past and has not been apart I doubt it's a "dime valve" issue.

As to manuals, DEERE keeps pretty close copyright watch on their newer manuals, and I don't think you will find one on-line.

The most reasonable ones from DEERE are the CD versions. You can order direct from DEERE by calling 1-800-522-7448.

I still suspect it's one of the coupler bodies. I suggest you swap 'em from the other side and see if they work before buying a $$$$ manual and tearing into it.

stoneridge · Jun 26, 2016

turned out to be the adjustment for the hyd speed on the spool.

I had taken apart the control from the top where the adjustment knob is but didn't realize there is a second section that can only be removed from the bottom of spool, behind the control cable.
there is a 2 piece body and a spring, the body had come apart and just needed to be threaded back together.

Thanks for all the suggestions boys.

jd 6400 hydraulics

stoneridge

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Bob

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stoneridge

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Bob

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stoneridge

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