4640 rock shaft valve issues

I am working on a 4640 quad range that broke the hex shaft for the trans pump, (the pump broke then broke the shaft).
It got a new pump and shaft, then after I got the rock shaft housing back on the rock shaft does not work right. If you move the handle to raise the rock shaft is raises the amount commanded, but continues to raise, creep up slowly, then will not go back down until you shut the engine off. I checked trans pressure, stand by pressure, had the valve apart several times, removed the entire valve from the rock shaft housing, checked hyd load control valves, tried to adjust rock shaft valve several times in both directions, nothing has change. What am I missing?
 
Strong chance you didn't get the cam follower lined up into the valve,, you can lift just the valve up off to deal with this..
 
This one has the hyd load/depth control cylinder on the RH side, I have had the valve housing off twice and the valve arm rides against the cam on the rock shaft like it should,unless I'm missing something, there's not really anything to line up like the smaller tractors that have the arm in the transmission case that you have to catch with the valve when you put it on
 

Are you referring to cylinder in photo below? If so that is a 3 pt lift assist cylinder that is controlled by 3 pt valves but has nothing to do with controlling the 3 pt.

mvphoto20101.png
 
No, I'm talking about the short, spring loaded cylinder, connected to the RH draft arm, as I have said this tractor has hyd load/depth control not mechanical.
 
Not familiar with those, but the parts book shows 2 tiny filters in the rockshaft load control valve (page 04D25).
Your problem could be related to them be clogged due to oi pump debris?
 
(quoted from post at 14:58:10 07/20/18) No, I'm talking about the short, spring loaded cylinder, connected to the RH draft arm, as I have said this tractor has hyd load/depth control not mechanical.

I was unaware the 4640 had hyd load sensing but not many of that model sold in my area. One learns something new every day.

mvphoto20218.gif
 
(quoted from post at 02:48:52 07/22/18) Not familiar with those, but the parts book shows 2 tiny filters in the rockshaft load control valve (page 04D25).
Your problem could be related to them be clogged due to oi pump debris?

Those 2 tiny filters aren't cheap but it states they have orifices in them.

AR77710 FILTER WITH ORIFICE ADD 22.47 USD
 

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