where to hook up new electric choke

[79malibu]

i just got a new specd carb from SMI in huntington beach, ca and i'm about to put it on the malibu but my 79 didn't come with an electric choke. so where should i run power to it from? a note card that came with it in the box said DO NOT hook it into the ignition wires. so would that mean i have to tap into the acc wires from inside and run a lone wire out through firewall to it?

 

[outsider_27]

Needs to be hooked up to a wire that has power only with the engine running. I have heard the oil pressure idiot light sending unit wire works well.

 

[joe_padavano]

Needs to be hooked up to a wire that has power only with the engine running. I have heard the oil pressure idiot light sending unit wire works well.

You hear incorrectly. The wire from the oil pressure sending unit simply shorts to ground (through the sender) when there is no oil pressure and is open when there is oil pressure. The factory powered the choke in one of two ways. Either a dedicated switched +12V wire was run through a separate oil pressure switch to the choke or a wire off the terminal on the alternator was used to operate a choke relay. Either one works fine. It really isn't very difficult to find an ignition-switched 12v source in the engine compartment.

 

[79malibu]

yea i figured that. any idea how much amps i need to run an inline fuse on the choke?

 

[beermonkey9417]

MANUAL CHOKE!

 

[Phoenyx]

MANUAL CHOKE!

X2

 

[jeff0547]

I tapped into the hot wire from the Windshield Wipers. Seldom are both used at the same time. Even so, it won't likely overload the circut.

 

[czar996]

I tapped into the hot wire from the Windshield Wipers. Seldom are both used at the same time. Even so, it won't likely overload the circut.

X2 It was close and only hot when ignition is on. Took about 10 minutes.

 

[joe_padavano]

The factory did it one of two ways. One is a special oil pressure sending unit that has three terminals - one for the idiot light and a pair that are connected to a switch that closes with 4 psi or more of oil pressure. The other way (which was used when the car had gauges) is to use the field wire from the alternator (the one that connects to the GEN light). This wire only has 12v when the alternator is turning. Note that in this case the factory used the field wire to close a relay that powered the choke. In both cases, the wire to the choke is fused at 20 amps.

As for the comment that you don't use the choke and the wipers at the same time, that's flat wrong. The choke draws power whenever the engine is running. If you drive in the rain, you are using the choke and the wipers at the same time. The risk of blowing a fuse is yours (and hopefully that's all you burn out).