JD 790 SCV repair

[zoot75]

Has anybody been successful fixing the selective control valve, (bucket control) problem on a John Deere 790 with 419 loader?

 

[kennyd]

What problems are you having?
There’s not much that’s serviceable in a valve body.

 

[zoot75]

The bucket will not lift, there was a repair kit available in the past but is no longer available now. The valve is expensive and if it is a design flaw then replacing it with a similar one will only prolong the problem. I have done all the usual checks with fluid, dirt clean etc. Other owners are having similar issues. John Deere is not helpful at all. I have an expensive piece of scrap metal now with only 240 hrs.

 

[Rock knocker]

Is this a joy stick operated valve located under the seat?

 

[zoot75]

It is the hydrolic control valve which operates the bucket, raise, lower, tilt etc. Lever is on the right side of the seat with valve directly under.

 

[Rock knocker]

It is the hydrolic control valve which operates the bucket, raise, lower, tilt etc. Lever is on the right side of the seat with valve directly under.

And operated by a weird series of linkages?

 

[RobS]

I have an older 790 with the 70 loader. Never heard of such a problem but that doesn't mean it doesn't exist. I hate to mention the obvious but have you verified that the lever lock out is open for both lever directions? It is a small lever at the base of the SCV lever. Beyond that, are all hoses fully hooked up?

If it's neither of those, I'm out of ideas. Might be something inside the valve?

 

[MORRISONSTEEL]

The bucket will not lift, there was a repair kit available in the past but is no longer available now. The valve is expensive and if it is a design flaw then replacing it with a similar one will only prolong the problem. I have done all the usual checks with fluid, dirt clean etc. Other owners are having similar issues. John Deere is not helpful at all. I have an expensive piece of scrap metal now with only 240 hrs.

The only kit I see (that isn't for centering or load check) is the seal kit, and it is still available. Now the valve itself did supercede but that may have more to do with it being the one used on 3005 (pretty much a 790) and 4005 cuts. At bare minimum this tractor is over 10 years old, does it actually only see 24 hours a year or has it spent a good chunk of it's life just sitting. The oil has to be going somewhere, do you know where it is ending up? As far as john deere not being helpful has an actual tech evaluated this tractor?