is my choke supposed to have a constant hot wire hooked to it?

 

No.

On most Fords around that year(1981) there will be a White/black stripe wire on the "S" terminal of the alternator, that's where the Choke wire hooks up.
The "S" wire runs to the 4 post Voltage Regulator's "S" terminal so Choke could be hooked up at that end as well, or there may be a splice in the "S" wire for the choke.
3 post Voltage regulator uses a different "S", in this setup choke will be hooked to alternator "S" for sure

This terminal will only have voltage when alternator is turning, so engine running, and it will have only 6 to 8volts.

 

thanks Ron, I do have a "hybrid" 81 truck with a mid-late 70's 400M series motor? any differences?

 

If it has an external voltage regulator then should be the same.

Electric choke is hooked to alternator because it is an "engine running" circuit, really the only one there is.
If choke was hooked to "key on" circuit then when you turn the key on the choke starts it's cycle of warming up and opening, now if you chose to talk with some one for 5 minutes BEFORE actually starting the engine then engine would run without full choke and maybe not start or run rough until it warmed up.
Because Ford didn't want to put a "Please start engine when you turn key on" sticker on the visor, they just hooked choke to alternator.

If you are aware of this then you can hook up the electric choke to a "Key on" circuit, if it is easier, I would use a relay, and just remember to start the cold engine after turning on the key, if you want to chat turn the key off, lol.

 

it wasn't hooked up when I started doing some maintenance on it. (had to replace the water pump, valve cover gaskets, fuel line) i reconnected it and truck was running for crap we figure it was engaging that choke with all the gas we were smelling and how my mileage went T/U. we disconnected it and it seems to be running way better.

 

These types of "automatic chokes" have a bi-metal spring that holds the choke plate closed, as it is warmed up, either by electric or exhaust gas the spring opens and choke plate opens.

Issue with these is you had to adjust them for winter and summer, and for spring tension wear after years of use.
There should be a large black plastic "cap" where the electrical plug is.
There should be 3 slotted screws holding the cap.
Loosen screws and with engine cold, and off, rotate cap so choke plate is just opening
Tighten screws.

If there are no screws, but there are rivets, they will need to be drilled out and replaced with screws, carb rebuild kits often came with these screws.

In the summer you really don't need the choke for more than a minute or two, but in the winter you will be glad you have it hooked up

 

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