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Discussion Starter #1
My over drive switch stopped working a while ago. It lost its springyness and didn't really do anything. I pulled the switch out of the shifter, and found a little folded piece of metal floating around in there. Its about the same diameter as the switch and I think its the part that joins up the contacts to operate the switch.

My question is, when I come to order new parts to fix the switch, is that piece part of the switch plunger or part of the other half that's fitted inside the shifter?
 

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Discussion Starter #2
Sorry, I meant the length of the small folded piece is the same size as the diameter of the hole in the shifter.

Can anyone help me?
 

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Discussion Starter #3

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While I don't know what it is considered part of, (the plunger or the contact in the well) I can at least tell you that the metal piece is called a dome switch. It works along the lines of the button on top of pickle jars, in that it pops when pressure is applied. I believe it is the only part that needs to be replaced. (Assuming the barbs on the plunger are not cracked, and the traces in the well are ok.)

The switch might be the same across Fords of the same era, so you may be able to find one in a car slated for the crusher.
 

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Discussion Starter #5
The barbs are OK, but I can't figure out how the dome switch (metal part) is supposed to be fixed in place.
 

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It's a simple momentary contact switch, marrying very little current.

Any switch you can fit there will work, pretty much; you could even do a covered toggle on the dash if you wanted. :)
 

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Discussion Starter #8
Ok, I opened my switch and there are no other parts. From what I can tell, the rubber piece on the plunger and the grooves in the well are what keeps the dome switch in place.
So when you take your plunger (with the rubber piece on the end) out of the shifter and look into the shifter hole, there is nothing in there that looks like the metal piece in my picture?

Once I'd hooked that part out, I could see the copper contacts at the back, but I can't see how the rubber plunger makes them touch together. To me it looks like there should be a flat metal end on the plunger so that when you push it into the hole, it links the copper contacts together.

I'd rather not rewire it so that I have another switch elsewhere on the console as the original one is in a pretty-much perfect location, in my opinion.
 

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My switch assembly does have that metal piece, only it isn't bent out of shape. it is supposed to look similar to this:



This metal piece is what touches the contacts together in the well. Normally, the metal piece has a dome shape (hence the name dome switch) to keep from bridging the contacts. When pressure is applied, it flattens out and touches both contacts, while giving the tactile feel. (the springiness)

 

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Discussion Starter #10
Thanks Lucifer. Very useful diagram! I understand how it is all supposed to work now. Somehow my dome has become mangled. I've no idea how.

I've been quoted approx $40 for the plunger part of the switch, and about the same for the part that fits into the shifter handle with the wires attached. I wonder which part includes the dome piece??

I'm beginning to think I may be better off trying to refurbish the parts I have. It seems like a lot of money for what it is.
 
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