Author Topic: How to replace ignition switch?  (Read 5026 times)

Offline bd

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Re: How to replace ignition switch?
« Reply #15 on: March 18, 2021, 09:49:17 PM »
1)  The center nut seats the adapter hub onto the tapered shaft.  As long as the splines and alignment ticks are lined up, just tighten the nut.  No need to pound on the hub.

2)  There are two designs of lock tumbler, early and late.  Did you compare the cylinders before swapping?  Do they match exactly (other than the thumb flags that were broken off)?
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Spool

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Re: How to replace ignition switch?
« Reply #16 on: March 18, 2021, 10:10:10 PM »
I did compare the two - they had their subtle differences, but were GM made and identical in size.

I placed the new one after seeing how there was a groove on the bottom of the column that lines up when inserting.

Offline JohnnyPopper

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Re: How to replace ignition switch?
« Reply #17 on: March 24, 2021, 06:41:13 PM »
Queue Willie Nelson "On the Road Again"!!  ;D

Nice work Spooler man!  8)
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Spool

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Re: How to replace ignition switch?
« Reply #18 on: March 24, 2021, 08:36:09 PM »
Thanks man.
Any thought on how to get the ignition lock back out? One day, Iíll have to, or even maybe sooner to do it correctly if needed.


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Offline JohnnyPopper

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Re: How to replace ignition switch?
« Reply #19 on: March 25, 2021, 11:15:33 AM »
It's been years since I was that deep into it, but the pic of the new one reminds me of what locks the cylinder in it's spot; the spring loaded black thingy toward the bottom. Can you get to that, depress it and slide the cylinder out?

Having a hard time understanding your hex question. Is it a bolt or a nut? Can you post pics of the area below the hub?

If it's all back together I guess the point is moot.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Spool

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Re: How to replace ignition switch?
« Reply #20 on: March 25, 2021, 12:09:08 PM »
Yeah- it is kind of moot.
The only point worth entertaining the talk of removing the new one is: is it so easy to remove that someone can pop it out and then just reach in with pliers to start it up.

Iíd have to take the whole thing apart again to see if I can depress anything.

But, and I wish I had a picture... the old ignition lock had a small groove machine out, which left clearance for the hex bolt to slide into place. The new ignition lock doesnít have that, hence why I gave up trying to get it in place- zero clearance.

Yet, something is holding the new lock in place- I just donít know what.


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Offline JohnnyPopper

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Re: How to replace ignition switch?
« Reply #21 on: March 25, 2021, 01:34:16 PM »
I get it now, sounds like the new one with the spring tab is what is locking the cylinder in place, that's why you couldn't pull it out.

The old one was keyed with clearance for a bolt that locked it in. I think your good to go, you can't pull out the new cylinder.

BTW, you just ran over a weakness in these ignition designs... you can hammer a flat screwdriver into the key slot, break the inside of the cylinder, turn the screwdriver and drive away. Yikes! #whatisatireboot
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Spool

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How to replace ignition switch?
« Reply #22 on: March 25, 2021, 01:56:48 PM »
I joke about this at times in saying, I could steal this thing with a screwdriver if I really wanted to.


Which is exactly why Iím researching kill switches at the moment before I start a new thread.

Iíll provide a teaser though: cigarette lighter kill switch. (Another step to get me to quit smoking too- two for one!)


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Offline bd

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Re: How to replace ignition switch?
« Reply #23 on: March 25, 2021, 02:04:03 PM »


Spool, you replaced a late-style tumbler (bolt retained) with an early-style tumbler (flag retained).  The original column was probably replaced with a newer design at some point.  Removing the old design tumbler from a new design column will be problematic, requiring a precisely placed square tip screwdriver tapped with a hammer to create a rectangular hole in the housing through which you can depress the flag.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline Spool

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Re: How to replace ignition switch?
« Reply #24 on: March 25, 2021, 02:31:04 PM »
How can you tell I have a new column?

And if so, are you saying I need to break the new lock to remove it?


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Offline bd

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Re: How to replace ignition switch?
« Reply #25 on: March 25, 2021, 04:25:03 PM »
I don't recall in which production year the migration to bolt-retained ignition tumblers took place, but the 1973 model year trucks had the earlier design columns that used flag-retained tumblers.  So, without additional information, I surmise that the column in your truck is not the original, but from a later model truck.

Hopefully, removing the new lock cylinder will only require a strategically placed screwdriver to create a hole in the right place of the housing to access the spring-loaded release flag.  The process sounds more worrisome than it actually is to accomplish.  It's simply a matter of recognizing the correct location to create the new release hole.
Rich
It's difficult to know just how much you don't know until you know it.
In other words... if people learn by making mistakes, by now I should know just about everything!!!
87 R10 Silverado Fleetside 355 MPFI 700R4 3.42 Locker (aka Rusty, aka Mater)

Offline JohnnyPopper

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Re: How to replace ignition switch?
« Reply #26 on: March 25, 2021, 04:38:40 PM »
A good kill switch will just disable the signal to the starter solenoid, I think.

I'd like to have a layer of insurance.

I can draw up a circuit where all you/we will need is a small magnet to bypass it.

Maybe bd knows the amperage draw of the solenoid is? Match a relay and we're good to go.

Just keep a few magnets around just in case... 8)
« Last Edit: March 25, 2021, 04:43:25 PM by JohnnyPopper »
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Spool

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Re: How to replace ignition switch?
« Reply #27 on: March 25, 2021, 06:19:39 PM »
Thanks BD. Iíll revisit this when I ever have to remove the ignition lock.

Johnny, Iím gonna start a different thread for the kill switch idea- Iím still researching and brainstorming where to put or which circuit to interrupt, but will def. ask you more about that magnet concept you just mentioned in that thread.


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Offline JohnnyPopper

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Re: How to replace ignition switch?
« Reply #28 on: March 25, 2021, 08:39:42 PM »
Ok man, I looked at the warehouse today, found a 12v triggered, 70 amp relay, ought to do it.

Will test my circuit theory in the meantime.

First thought is to interrupt the starter solenoid wire with a relay.
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction

Offline Spool

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Re: How to replace ignition switch?
« Reply #29 on: March 25, 2021, 08:53:21 PM »
Yeah - good idea on the starter. I'd like to pick your brain about that.
I just started the other thread in the electrics area.