Fellows 100" gear shaper service info urgently needed.

If you are familiar with this piece of equipment, I need your help. When the cutter comes down, making the initial cut it is at a 90 deg angle to the work piece. Upon the up stroke the part of the cutter drops down to avoid contacting the blank. Mine is stuck in the 90 deg position.
Brough and Kough claims they have no Maintenace manuals or hydraulic schematics.
Since this is the only hydraulic operated component on the machine, and I have no maint. manuals. My plan is to start at the pump and work forward, this unfortenatley this leads to the selector valve for internal or external gear production. Since I have no documentation on how this is supposed to work, I hesitate to take it apart.
Anyone with suggestions or ideas I would really appreciate any ideas or options. Machine is down, and 3 gears on the way.
Machine has no serial number, just a tag circa 1944-45 war time finish.
Tried to give a simple explanation of the issue. Please feel free to ask question if I missed anything.
I pulled the cover from the hydro tank and found what appeared to fibrous material like valve packing. When the malfunction occured I was not present, from what I was told the cutter stalled in the middle of the cut. They put a 5 foot snipe on the manual knob and removed the cutter to up position. So frustrated
Thanks

Curious to know what "a 5 foot snipe" is doing in the shop. That's a big bird!

Have no idea about your machine.

Thank you, David,
Now I have a starting point.

Millan,
I always photograph equipment that I am reverse engineering or just doing routine maintenance. But with this your suggestion of a photographer is great. NO more fiddling with camera and 100% concentration on the job.
Love it,
Thanks