WTB American Bosch Magneto switch

[Gotfredson]

Looking for a switch like this in operating order:

 

 

I don't necessarily need a key.  The keys in the photo are not original, however, they were made to fit.

 

Alternately, is there anybody who might be able to fix the one I have in the photo?  The internal spring action is broken and it seems the structure of the housing is pressed together.

 

Old post I found here, but already sold:

 

http://forums.aaca.org/topic/128247-for-sale-american-bosch-ww1-era-magneto-switch-possibly-nos/

Edited December 16, 2015 by Gotfredson (see edit history)

[hddennis]

Can also use Bosch S 12.

Howard Dennis

[Layden B]

If anyone is interested, have this magneto switch ( makes in OFF position to ground and kill a magneto) 2 3/4" diameter, works great. $165.

 

 

[Gotfredson]

Took it apart.  Destroyed it as expected.  The internal spring was broken.  If you ever try to take one of these apart to fix it keep in mind...

 

1) The spring is usually the first thing to go.  You will need to find a spring with the exact same width and length to fix it.

 

2) The center mechanism is made of brown PLASTIC, which is very brittle.  Be careful taking it out or it will break into pieces.

 

3) Do not cut along the lines of those two indentations (like I did).  You want to keep those indentations intact.  They hold an internal washer in place:

 

 

 

 

 

 

See here the spring is broken in half, which is why the switch was not working:

 

 

 

The brass T is what makes contact with the brass washer to make continuity and kill the magneto.

 

 

[Gotfredson]

[Gotfredson]

Superglue worked on the broken plastic part.  I am back in business:

 

 

 

Found the right measurement compression spring on Ebay -- 20mm long by 5mm wide.  $2.99 !

 

http://www.ebay.com/itm/10-Pcs-Small-Compression-Springs-20mm-Long-x-5-mm-OD-/331704124039?hash=item4d3b1b4287:g:~mgAAOSwu-BWQQCm

[Gotfredson]

The superglue did not hold and the brown plastic part exploded when I tried to bend the metal back around it.  So, I ordered a piece of black plastic rod off ebay with the same diameter:

http://www.ebay.com/itm/1-pcs-Nylon-Polyamide-PA-Plastic-Round-Rod-Stick-Black-20mm-x-250mm-B-F-/171427628569?hash=item27e9e20619:g:NUsAAOSwDk5T9EuS

 

 

Cut it with a hacksaw, drilled it out, and grinded it with a dremel.  It was much stronger plastic than original.  Installed the new spring I found on Ebay too.  I was able to pound the metal back around the new black plastic.  There also is a metal band that goes around it for added support.

 

 

Works like a charm.  Front of the switch is fine:

 

Edited January 12, 2016 by Gotfredson (see edit history)

[1912Staver]

Thanks for the excellent photo's. Often with delicate components like this getting them apart without major destruction is the biggest hurdle. Your photo's should be a big help to anyone with a similar switch that needs repair.

 

Greg in Canada

[Guest patdbossct]

On December 15, 2015 at 6:09 PM, Layden B said:

If anyone is interested, have this magneto switch ( makes in OFF position to ground and kill a magneto) 2 3/4" diameter, works great. $165.

 

 

Do you still have this for sale ?