1953 Buick Super 322 Nailhead V8 - replacement for carburetor accelerator vacuum switch?

[NickPlymouth]

Hi all,

I'm having to replace the carburetor which means I will loose the accelerator vacuum switch. Therefore it will no longer start by depressing the accelerator pedal. I could put a simple push button start switch in, but has anybody got a method that would still work off the accelerator pedal to keep the experience authentic?

 

Can I attach a separate vacuum switch? If so, what switch?

 

Thanks.

 

Nick

[Frank DuVal]

The vacuum does not activate the switch, simple movement of the throttle linkage inside the carburetor activates the switch. The vacuum keeps the switch from activating, it is a safety interlock along with a connection to the generator/voltage regulator.

 

Have you looked for an original carburetor with the switch? 

 

 

[NickPlymouth]

Thank you Frank. 

Yes, I forgot to mention the "activation" switch. That bit is relatively easy but I stopping it from trying to crank if the engine is already running is the more tricky bit. 

I haven't managed to find an exact match to the original, but I plan to convert to EFI soon anyway. 

Nick. 

[Bloo]

A normally closed vacuum switch would do the job. I don't know offhand where to get one.

 

[Frank DuVal]

Well, a vacuum switch by itself will not help, as when you  floor the accelerator the vacuum drops to zero. That would engage the starter if the vacuum switch was the only interlock. 

 

The original system used the voltage regulator as the second interlock. Floor it and the generator still has output, so the starter does not engage.❗🛠️🚕

[Bloo]

He'd also need a throttle switch, but i gathered that part was already solved. I would expect the generator interlock to already be present on a 53 Buick.