Moog Fail safe not working

Good day, Can i change the Fail safe for Moog D638..
I use the Moog Software to calibrate the Zero and Span..

But the issues now is if you remove the Power the failsafe is suppose to close the valve slowly, But instead it opens the valve to maximum Open.
 
Good day, Can i change the Fail safe for Moog D638..
I use the Moog Software to calibrate the Zero and Span..

But the issues now is if you remove the Power the failsafe is suppose to close the valve slowly, But instead it opens the valve to maximum Open.
Once the power is removed the integral electronics can't apply any signal to the proportional magnet.
The only way I can imagine you can set the bias is: unplug the electrical connector, turn on the hydraulics, remove the big hex nut on the end, (there will be no leakage) slacken the tiny nut and with a small Allen key adjust to get the small bias.
This is a bit tricky because tightening the tiny nut effects the setting so you might need to try this a couple of times.
I'm assuming you will be doing this with the valve attached to a cylinder.
Basically you are setting the spool position in the absence of power.
 
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