Did my ignition switch just go out?

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wanderinthru

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84 K 20, 350, 465. Jumped in it to go have steaks with the lady friend, fired right up and off we go. About a mile from the house look in the seat, have a jacket, have a bottle of Johnny Walker...no steaks. Turn around, come back to the house grab the steaks, hit the key, nothing? Do it again, nothing. No radio, no gauges, no crank. Jump the red and purple wire and it cranks but no fire. Unless I've missed one all the fusable links have been removed. plus the big red wire is hot at least out side the firewall. Studied the wiring diagrams and all I can see common is the ignition switch, it has been acting funny and I was blaming that on the key tumbler, not the switch? The head lights work (wasn't dark so didn't notice the dash, plus I was ready for a drink and a steak) Have another project to finish this morning then I'll be out checking stuff. This is a new one for me, reckon I'm on the right track with the ignition switch?

Thanks
Shakey
 

wanderinthru

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Switch perhaps. If the key works, not a tumbler problem. Maybe the switch has moved out of position?
Tumbler feels right? Don't mean it is right! Thanks will check that first.
 

75gmck25

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First a little trivia - where is the ignition “switch” on your truck?

The keyed switch on the upper column is just the key cylinder and a few other parts, and all the electrical parts of the switch are mounted lower on the column about where the column goes under the dash. Connecting the key switch to the electrical switch is an ignition rack and rod that is used in nearly all GM vehicles of that vintage.

If the small rack connected to the end of the key switch breaks/cracks, or the rod running down the column gets bent, when you turn the key it may not move the electrical part of the switch to the proper position and you can’t start the truck. You can get an inexpensive repair kit ($15?) for the rack (just search for GM ignition rack), but it requires quite a bit of column tear down to replace it.
 

wanderinthru

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Well, to be more accurate, and maybe feel less stupid. I forgot there were 2 fuses, so when the starter ran I figured I had power...nope. Full discloser, and to take away any redemption the first statement may have provided. As I think about it, ain't the first time this fuse has blown. Though the first time I didn't publish it to the world, lol. I can laugh at myself, provide myself the reason to do so pretty regular.
 

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Yo! Shakey! Whuts up with the durn thang?
 

WP29P4A

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Well, to be more accurate, and maybe feel less stupid. I forgot there were 2 fuses, so when the starter ran I figured I had power...nope. Full discloser, and to take away any redemption the first statement may have provided. As I think about it, ain't the first time this fuse has blown. Though the first time I didn't publish it to the world, lol. I can laugh at myself, provide myself the reason to do so pretty regular.
Any chance the fuse that blows was originally a fusible link?
 

wanderinthru

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Engine Size
350
Any chance the fuse that blows was originally a fusible link?
If your asking did it replace a fusible link, yes one down at the starter. Truck has headers on it, they were being awful hard on the wires as they ran down the frame back to the starter. So, I rerouted all those along the firewall to the battery. Replaced the links with fuses.

Edit to add: The fusible link had never broke. Didn't check specs, just put a 30 amp fuse in it.
 
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wanderinthru

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Mid Point Route 66
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81, 70, 75, 84, 89
Truck Model
K 10, C 30, K 20
Engine Size
350
Yo! Shakey! Whuts up with the durn thang?
Probably the mechanic! Change the blowed fuse fer one that ain't and off we go. Well till the water pump went out in my other not broke truck, then the fuel pump went out in this one? 4 legal trucks around here and couldn't go nowhere in one of them. Have a couple non insured, not tagged or stickerd ones I went with though.
 

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