How to unstuck power shift valves?

[Sparffo]

I have now quite a problem with my D6C 83A! I opened a tread about it previously, but now i opened a new one, because this could happen on any PS tranny...
The problem was that there was water in the gearbox, and it has been standing for many years.
I figured out that something is stuck due to corrosion or beginning rust, but what?
This is what i have done, in this order:
- cleaned the metal screen filter and the magnet
- changed the preassure side paper filter
- opened the relief valves on the torque divider, and unstuck the valve spools (some where stuck)
- tested the preassure, it's barely above minimun readings
- put some diesel fuel in the oil, to make it thinner and maybe losen some rust

Next step will be to drain all the milky oil and i was thinking about cleaning it out, with running diesel fuel in it for a while?

Is there some valves inside the gearbox also? The spare parts manual says there should be something called "preassure control group", but I can't locate it outside the gearbox?? Is it inside? If they are stuck also... :bash:Banghead

 

[D6c10K]

The pressure control valve and the selector valve are under the top cover of the trans. E-mailed some info on removal and testing of valve.

In the selector valve there is a safety valve that prevents trans from engaging if pressure is below 100 psi...if you have low pressure for some reason that may be why is won't engage at all.
If you haven't done so, I might pull the top cover and see what things look like...if it's had water in it for a long time it might be pretty nasty.