vacum vs. electrical
Thread Starter
Instructor
Joined: Sep 2005
Posts: 122
Likes: 0
vacum vs. electrical
I just bought a 1970 convertable . this is my first of this style, in the past I have had 1962s so this is all new for me. My first question is how does the electrical system let the vacum system know when to activate one of the many acctuators or is it the other way around?
Any help would be great as I am new to this era vette
Any help would be great as I am new to this era vette
Le Mans Master
Joined: Jul 2005
Posts: 5,752
Likes: 4
From: Austin Texas
The headlight vacuum system is activated by a vacuum switch mounted on the headlamp switch. The wiper door vacuum is activated by an electical vacuum valve mounted on the back of the tachometer. There are vacuum over-ride controls mounted just below the steering column, at the lower dash pad. these allow you to open the h/l or wiper doors without actually turning them on..G/L 
Melting Slicks
Joined: Jul 2002
Posts: 3,000
Likes: 22
From: Boulder Creek California
Alot of the vacuum parts are analogous to electrical equivalents. Electrical or vacuum relays, electrical or vacuum switches, electrical or vacuum 'hoses' 
Vacuum reservoir = electrical capacitor.
Vacuum reservoir = electrical capacitor.
Drifting
Joined: Nov 2001
Posts: 1,469
Likes: 6
From: 68 427 4.11s Roadster
To turn on vacuum with an electric switch. A solenoid like your door lock solenoid only very tiny moves a valve. Air either flows or not depending on design.
On mine the wiper door is activated by the electric wiper switch not by a vacuum switch, or valve. I think yours is too.
Same for the wiper arms. Parked or not. This switch does tell the door its safe to close. Activates vacuum flow the other way.
They don't use this one.
To turn on electric with vacuum. You reverse the above and use a air solenoid to operate an electric valve.
a Vacuum motor closes or opens the switch. Can be built many ways but basicly thats all its doing.
I think both are called transducers. Items that translate mechanical to electrical or vica versa. They don't have to be on/off but can vary. A potentiometer would vary voltage for some hair brained function.
OOh ooh. Your oil pressure idiot light is a pressure to electrical switch.
The senders on newer cars would vary. Oil pressure for examp. senders are actually transducers, that is if I'm remembering the term correctly.
On mine the wiper door is activated by the electric wiper switch not by a vacuum switch, or valve. I think yours is too.
Same for the wiper arms. Parked or not. This switch does tell the door its safe to close. Activates vacuum flow the other way.
They don't use this one.
To turn on electric with vacuum. You reverse the above and use a air solenoid to operate an electric valve.
a Vacuum motor closes or opens the switch. Can be built many ways but basicly thats all its doing.
I think both are called transducers. Items that translate mechanical to electrical or vica versa. They don't have to be on/off but can vary. A potentiometer would vary voltage for some hair brained function.
OOh ooh. Your oil pressure idiot light is a pressure to electrical switch.
The senders on newer cars would vary. Oil pressure for examp. senders are actually transducers, that is if I'm remembering the term correctly.
Last edited by Techno; Sep 23, 2005 at 09:18 PM.
