51 GMC dash questions

[bobs51]

Hi and first thanks for all the helpful feedback. I have an interesting thing in the dash of my 51 GMC truck. I pulled the gauge and speedometer and when I did the following switch fell out. (it's the one with the white knob). I thought it might be the blower but not sure. The reason I'm not sure is that there aren't any free holes on the dash.

My second question is about the knob labeled 'T' under the choke. If you look at the picture you see that it doesn't do anything, it's just a tube like device that is crimped at the end. I was thinking that maybe it worked the windshield wipers but at this point in time there is nothing attached to them (there was a coat hanger which I really think is wrong ).

Thanks for any feedback.
bob

 

[Bill Hanlon]

The switch with the white knob is NOT a factory supplied part. Some previous owner may have had it hooked to the heater blower.

The "T" knob was originally a manual throttle connected to the carburetor in a similar manner to the choke cable.

 

[coilover]

The "T" knob is for throttle. You could have your engine run at any speed by how far you pulled it out. Was usually used in cold weather to hold the engine a bit above idle till warmed up. I have, on long trips, used the throttle to maintain highway speed while working the cramps out of my right leg but it is a "suicide" cruise control since it doesn't shut down when the brakes are applied.

 

[bobs51]

Thanks Bill and Evan, I see that our sponsor carries the throttle so I'm adding that to my list of stuff to replace.

 

[vwnate1]

Mystery Switch

That's a vintage aftermarket variable speed fan switch ~ it's long so the heat it generates doesn't cook the paint off the dash board .