Allison v730 will not shift out of first

[luvrbus]

1st do you have a air throttle ?

[Winging it]

I do not have air throttle.

[luvrbus]

The modulator is at the rear of the transmission on the curb side with a cable  that goes up to the throttle

[Winging it]

All right I will check it and get back to you

[olebusman]

Get your book out and look for the governor screen. Its inside a port with a plug just above the oil pan at the driveshaft end of the trans. It is a small cone shaped screen.  olebusman   btdt

[Winging it]

I think this is the modulator it does have a cable going up to the throttle linkage. What can I expect even I remove it and what should I look for. There are no air leak to the transmission.