| 120V intermittent mystery solved [message #305089] |
Sun, 07 August 2016 18:29 |
LarryInSanDiego
Messages: 336
Registered: September 2006
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Senior Member |
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43 year old 120V circuit breakers I just replaced with fresh ones after completely cleaning and deoxidizing the inside of the breaker panel from our '73 GMC. From the front of the panel, these looked and operated perfectly normal, but now it's obvious why I had intermittent function of anything 120V. The middle one is the closest to being anything near almost undamaged. This must have occurred long before we got this as this must have made quite a scene when it happened. The breakers checked fine from the outside, but there was no clue about this electrical armageddon until I actually pulled these breakers. That's when I noticed rust on the INSIDE of the breaker box, including where these breakers made contact (the center one is what they're all supposed to look like).
Root cause? Not draining the fresh water system in freezing weather. The chain of events worked like this: The exterior utility door is immediately behind the inside breaker panel. Of course, both external electrical and fresh water hookups connect there. As the copper piping burst on the inside right next to the breaker box (I had never pressurized it), some must have sprayed into it through the edge of the cover . Corrosion took over causing increased resistance and consequent localized heating. Complete disassembly, liberal use of phosphoric acid to remove rust (I didn't have Coca Cola laying around), lots of sanding and cleaning, a few update details, and the electrical system magically works perfect for once.
And yes, I do plan to replace all copper with PEX. And RELOCATE all electrical with something along the lines of a PD4560. What a pita to work with the oem location.
Larry Engelbrecht
San Diego, CA
'73 26' ex-Glacier
TZE063V100319 03/07/73
[Updated on: Mon, 08 August 2016 11:59] Report message to a moderator |
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