2007 3520 Power Reverser won't move

[Zebrafive]

I have completely reassembled. The components for items 1-4 above appear very simple with no damage.

Current symptoms are as follows: no forward/reverse, and also no PTO. The PTO may have been not working originally - I did not test it before the first tear-down. This may be a clue.

Forward test port results per spec.
Reverse test port results per spec.

Lubrication test port reads about 35 psi with the clutch in and 0 with it out while the machine is in neutral. When the clutch is pushed in it jumps to 35 right away, but when let out is slowly drifts to zero. With the clutch out and the machine placed in forward or reverse, the pressure goes quickly up to 35 psi, then drifts back down to 5.

Does this data provide some helpful direction?

Power Reverser in Neutral, lube should not have pressure, clutch in or out. The pressure you see with it out, might be a spike from clutch valve change? Or some internal leakage opening the lube cut off valve?
Lube pressure will vary when in F or R due to the modulation valve.

 

[tuolumne]

Here are some schematics that might be more helpful. The lubrication oil to the reverser valve actually flows through the steering control first.

 

[tuolumne]

I don't have fittings that would allow me to test hydraulic pressure at the PTO supply line, but it does come out amazingly fast when opened! I was able to plug that line and test the reverser valve with the same results as previous. I wondered if the PTO valve was somehow dumping so much hydraulic flow that the reverser valve did not have enough to function....this is not the case. But why is the PTO out also? Is it possible that there is a mechanical failure at the main input shaft that brings power to the drive gears and the PTO? What can be tested (manually turning things) before splitting the machine to find out?