When I bought my type 30 in 1972 it had a hole in the dashboard that had two smaller holes above and below. I assumed it was for some sort of switch and later noticed other type 30s had an identical arrangement with some sort of "socket". I later saw an item on Ebay that seemed to be such a switch. I bought it, and when it arrived I saw that the key was stamped 1254 which was the serial number of the Brescia owned by the father of the person who sold it to me. I was perplexed however because there did not seem to be any mounting holes. I subsequently bought another switch and key on Ebay and this one had no obvious mounting holes. I have just bought a third one! The seller thought it came from the Molsheim spares. It does have the two holes threaded and fits perfectly into the hole in my dash.

So I have three questions:

1. How were these switches attached on Brescias (I've never seen one on a Brescia)?

2. The key transmits a hefty shock when you pull it out to kill the ignition, is this a Bugatti design feature?

3. Was there a stock of these in the Molsheim spares?

more photos

Did you buy it from a realy nice english chap called Jess?

If so answer to Q3 may be No,
Jess is no Bugatti expert but he is honist and sells in good faith based on a description his dad(must be 80 now) gives him. He had retained a lot of old parts given to him when he maintained Hugh conways cars.

jess almost always lists his ebay bugatti parts as ex molshim stores.

some of these are certainly ex molsheim stores.Hugh Conway showed me the stock when it was stored in the garage of his mews london flat.

Anyone info on the seemingly open contact when pulling the key? Looks like a uhhh, shocking experience...

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Vive la Marque !!

I am no electrician but wouldn't a condensor between the wiring and the switch solve that problem ?

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"Barttore has left the forum"

if it you acting as an earth on disconnecting, why not wrp an insulating material around the pull area.keeps it original-as it can be removed- but avoids the shock...

The big question is: Is this a "design feature" or is there something wrong in the switch?

Skiff could interchange the switch with another, and try again. If there is no shock, then "the switch with the three mounting holes" might need an overhaul.

_________________
Vive la Marque !!

Yes, I bought the third switch from Jess. I have insulated the end of the key to avoid further shocks.

Thanks,
Skiff

Sounds like you're acting as the ground for the ignition wire.
Insulating the key end may be preventing you from getting a shock but that doesn't mean the problem is actual solved.

I believe that all Brescia models and the T.30 were originally fitted with magneto rather than coil ignition. Stopping the engine was normally by earthing the magneto and many mags, had an external wire connection post to make this possible. On my 1925 T.23, bought in 1957, all the electrics except the mag. were Marchal/Marchal-Vaucanson. They included an 'ignition switch' instrument panel, activated by a key. This key didn't turn, it only pushed in or pulled out. The switch itself consisted of two blade contacts, one of which was insulated from the rest of the switch but included a wire connection post. This wire led to the mag. earth post. The second blade was electrically continuous with the switch body, instrument panel, bulkhead etc. and so was part of the car's general earth. The two blades were normally in contact and so the mag. was normally earthed and inoperative. When the key was pushed in, it pushed the earth blade away from the mag. blade, so breaking the contact, de-earthing the mag. and allowing it to work. The key itself was always earthed and so never live or capable of giving a shock.

I'm not sure how 'your' switch works but the discussion so far suggests to me that it is indeed a mag. earthing switch, incorrectly connected/used in some way. Two possibilities come to mind immediately, there may be others:-
1. It is wired back-to-front in some way, possibly by being fastened to the panel 180 degrees out.
2. It has been wired into the live side of a coil conversion set-up, thus always leaving the key itself live - but the switch will still work to allow or kill ignition.
But I could be wrong.

I would like to know much more about the switch - such a lovely period piece. Does the key turn as well as push in and pull out? What are the functions of the slots in both the key and the switch body? Is the relative alignment of these slots fixed/important in any way? Are there any internal electrical connections to the instrument panel, either thro' the fastening screws or in some other way? It intrigues me!

My M-V key had disappeared before I bought the car and so I fitted a 'temporary' tumbler switch to perform the same function while I looked for a replacement key. After all these years, I'm still looking! I would therefore very much like to buy one of your spare switches so that I can:-
1. Have all the fun of finding out exactly how such a lovely piece actually works.
2. Fit it to my car as a far more appropriate part than the current device.
Any chance?
Cheers, Creweman.

Dear Creweman,

I followed the various suggestions regarding the ignition switch and insulated the key, however while driving the car one day I saw sparks arcing between the key and the air-pressure gauge bezel! I have since rewired the switch between the battery and the ammeter which seems to have worked, no more sparks.

I believe only the early type 30's had magneto ignition, all the later ones were distributor and coil ignition which means the switch did not serve to ground the magneto.

I am still unclear about how the switches were attached to the dashboard of the Brescias since two of the three switches I have seen have no place for mounting hardware. Conversely the type 30's that I have seen all have the two mounting screws at 12 and 6 o'clock.

Thanks,
Skiff