1952 master switch replacement

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BernieS
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Joined: Thu Sep 15, 2022 11:59 pm

1952 master switch replacement

Post by BernieS »

Does anyone have experience replacing the master switch (piano key style) in a 1952? After looking extensively at parts drawings and crawling around under my panel, it looks like a huge job. Thanks in advance for any assistance.
Bernie
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Bruce Fenstermacher
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Joined: Tue Apr 23, 2002 11:24 am

Re: 1952 master switch replacement

Post by Bruce Fenstermacher »

Bernie, it's been a while since I was under my 170 panel. You are right, the job takes some thought, is tedious cause your laying uncomfortably on your back while trying to see stuff in you by-focals that you can't get your head in the right position to do so. Not to mention working one handed.

Assuming the screws are original your looking as slotted screws. Getting them out is the easy part, replacing they isn't. For this job, split screw drivers are the key to not loosing your mind. If you haven't used them before, the blade is split and the knob on the shaft spreads the blade to wedge it in the screw slot, holding the screw. You can't use these screw drivers to loosen or tighten the screw though.
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Match sure your battery is disconnected. Remove the electrical bar strapping from the adjacent switch. Get up in there and carefully remove the nut from the master switch which may require some thin wrenches, I don't remember. Remove the switch and replace with the new and reverse the order of disassembly.
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n2582d
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Joined: Mon Apr 29, 2002 4:58 am

Re: 1952 master switch replacement

Post by n2582d »

Bernie,
To remove the switch bar bracket without removing the plastic overlay you’ll need to drill two small holes in the plastic as discussed here. A small magnet might help in locating the screws/where to drill.
Gary
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