something isnt right with the ignition key

[79K10]

so heres my problem. when i bought the truck, the PO said the truck would just shut off on its own, would restart and later turn off again down the road. so i figured out if i held the ignition forward like i was going to start the truck and hold it there it would stay running just fine.

So i went and bought a new key switch, installed it... and it still Fn does it! wth? it has to be in the column right? oh and its a pita to turn the key back to the off position as well (just like the old key was)

so my question is, does anyone know if i need a new column to solve this issue? is it beat to hell inside the column?
can i just put a switch somewhere under the dash to power the ignition and just use the key to unlock the steering wheel and start the truck? basically hot wire this thing so it doesn't keep shutting off going down the road maybe? my guess is its killing power to the dizzy, i mean it shuts off instantly if i hit a bump and the key nudges back.

thanks for any ideas or help!

 

[84ShortBox]

I would check the wires going to the distributor if you haven't already, could be a loose connection/ broken wire?

 

[72chevy2door]

It's your ignition switch. It is connected to your ignition key cylinder via steel rod. Last time I bought an ignition switch it was like 17 dollars for a quality one. It's bolted to the steering column on the top side. PITA to get to with big hands unless you unbolt the column from the dash (2nuts). But it shouldn't take no more than 30-45 mins from start to finish.

 

[chengny]

The ignition/steering wheel lock cylinder and the actual ignition switch (i.e. the electrical part) are not near each other. It goes without saying that you know where the lock cylinder is - it's pretty obvious and you have changed it out yourself. It is up near the top of the column on the right hand side.

The electrical switch is down further (almost even with the front of the dash) and is mounted on the top of the column.

Here is a page from the 1973 service manual that describes it's position and operation :

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An exploded view of a 1973 column:

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The lock cylinder has a pinion gear on the end that engages a toothed rack which is connected to an actuating rod. The actuating rod is what ultimately operates the switch. Here is a picture of a later model - I couldn't find an example of a 73. This version is not exactly like a 73 (the design of the link between the rack and rod is different), but the concept is the same:

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My point is: the issue you are having with the loss of ignition may well be related to either the linkage or the ignition switch itself.

You might want to drop the steering column and inspect the switch and the end of the rod. Unfortunately the rack, link and most of the rod are buried in the column casing.

 

[79K10]

It's your ignition switch. It is connected to your ignition key cylinder via steel rod. Last time I bought an ignition switch it was like 17 dollars for a quality one. It's bolted to the steering column on the top side. PITA to get to with big hands unless you unbolt the column from the dash (2nuts). But it shouldn't take no more than 30-45 mins from start to finish.

ah yes that sounds like a plan, thanks for the info! im relieved its an easy fix with a cheap part. I have fat fingers, so yes ill be unbolting the column hahah...
should i replace the steel rod too? would that be whats binding up when i try to turn the key off?

im gonna hit this in the am and hopefully take it for a spin. i bought a tire so beside the seat not being bolted down, lol, i should be good to go.

oh yeah then theres the master cylinder thats shot, rusted to hell. I did pretty much get a free master cylinder at autozone because i had 5 reward points, boom!!
you can see how bad it is in this pic... lmao, there were two water bottle safety snaps under the clip holding it down harder, the gasket is shot! ill post some more pics of it tomorrow, its hilarious

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[79K10]

The ignition/steering wheel lock cylinder and the actual ignition switch (i.e. the electrical part) are not near each other. It goes without saying that you know where the lock cylinder is - it's pretty obvious and you have changed it out yourself. It is up near the top of the column on the right hand side.

The electrical switch is down further (almost even with the front of the dash) and is mounted on the top of the column.

Here is a page from the 1973 service manual that describes it's position and operation :

You must be registered for see images attach

An exploded view of a 1973 column:

You must be registered for see images attach

The lock cylinder has a pinion gear on the end that engages a toothed rack which is connected to an actuating rod. The actuating rod is what ultimately operates the switch. Here is a picture of a later model - I couldn't find an example of a 73. This version is not exactly like a 73 (the design of the link between the rack and rod is different), but the concept is the same:

You must be registered for see images attach

My point is: the issue you are having with the loss of ignition may well be related to either the linkage or the ignition switch itself.

You might want to drop the steering column and inspect the switch and the end of the rod. Unfortunately the rack, link and most of the rod are buried in the column casing.

that's super helpful! thank you! I hope its the easy fix! lol ... im gonna pick up the switch in the morning

 

[72chevy2door]

No you don't have to replace the steel rod. Unless it's bent out of its normal shape. (Be aware it actually does have bends in it to accommodate to the design of the column) another words just unbolt the old switch and bolt up the new on and test to make sure everything works right and bam your done.

 

[79K10]

Thanks a lot! That was it! I replaced the switch, fires right up and doesn't turn off unless I turn the key off. All the binding up has also been resolved ,4 bolts, 2 nuts, 2 screws and it was out. Took about 15 minutes ... I'm stoked! Took my kids for a ride. They loved it! Too bad I can't say the same for my wife hahahaa


so i found the switch, the wire was a little worn but i didnt want to replace wiring if i didnt have to

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found this guy while i was under there too. Ill have to follow these and see where they go, unless someone knows off top?

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not quite sure whats going on here, the blower was coming on very low when i turned the key on. i ended up unplugging the blower motor

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im not liking the little air cleaner... i tried my full size one and it hits the dizzy ... looks like ill have to find a new one... i did reset all 4 mixture screws, turned em all in, some were at 2 turns out, and the last one was at 1/2 turn ... i backed em all out 1.5 turns and also lowered the float at the front, raised the back float. it fires right up most of the time now... the other day i turned it off and it seemed like the carb was still spraying into the motor, hopefully the float adjustment fixed that... still need to time it and change the oil. speaking of oil, i bought a new dip stick but it doesnt seem to be right, the hole in the block is way down close to the pan, im pretty sure the one in there now is the wrong one, so i really need to drain the oil and fill it back up to check the actual reading... well i drove it around the block and i can really tell it needs to be timed, and there is still a slight hesitation, maybe accelerator pump needs a turn or two on the nut? im sure my neighbors loved it today while i was reving the motor up hahahah

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theres the new part, you can only see a little of the new blue switch with those 2 screws holding it to the column

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glad thats done!! on to the next task

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