Help with Air Throttle

[pattypape]

We fired up the Bird, after not running it for about two months,
and we have no foot throttle acceleration.

Our 88 FC has a Williams air control foot trottle.
And a Bendix Cruise Controll.

Both the foot throttle and the cruise control, share the same air
throttle cylinder.
This air cylinder with the attached cable to the injection pump,
works great, for the high / low idle, that is set by the Resume/Set
switches on the Bendix Cruise.
The foot brake also lowers the idle.

It appears that the Cruise control is out of the circuit
when turned "Off". The cruise worked great on our last trip.

So is there a check valve or air solenoid switch in the air plumbing
between the air supply and the foot throttle?? Where is it located??

Any help or ideas are needed and welcome.

I was able to get some information from the drawings, that Ralph has
in the files.
But these seem to be for a 6V or 8V and may be different than our FC.

Bill 88 FC Michigan