Hook up electric choke? [Archive] - Chevelle Tech

: Hook up electric choke?


wildman704
Jan 8th, 02, 8:42 AM
I am installing a 750 dual feed w/electric choke. I have been told not to use the coil as the power source for the choke. Where do most pick up power for the electric choke on the firewall side or do I go to the fuse box?

------------------
Tom (Wildman704)
72 Chevelle SS454
67 Camaro Super Street
runs 10.3's @ 130 mph
01 Vette
98 Ram V10 (tow truck)

cjlandry
Jan 8th, 02, 9:06 AM
I go to the fusebox, but you can also tie it in with the wipers. When you turn the key on there's a wire that's hot all the time on the wiper motor. The switch just completes the circuit to ground.

------------------
My Web Page (http://www.landry-family.com) (updated 11-24-01)

"America will endure!"

Chad Landry
TC Member #643
ACES Member #04556
'68 El Camino

wildman704
Jan 8th, 02, 9:43 AM
Thanks cj. Do I need fuse protection if I go to the wiper motor?

------------------
Tom (Wildman704)
72 Chevelle SS454
67 Camaro Super Street
runs 10.3's @ 130 mph
01 Vette
98 Ram V10 (tow truck)

Coppertop
Jan 8th, 02, 11:19 AM
I would recommend NOT connecting to the wiper circuit. Most people don't realize the washer wiper circuit is HOT when the key is in the ACC (accessory) position.

This means, if you forget and turn the key to the ACC to listen to the radio while sitting in a parking lot, you'll fry your choke as it will also be getting power.

Your best bet is to isolate a "only hot when the ignition is on" circuit. If you can't find one, run a wire (I'd recommend 16 ga. at least) thru the firewall to the IGN terminal on the fuse box.

John_Muha
Jan 8th, 02, 12:02 PM
Ok, Since Carbs are not my strong point at all. Why does the electric choke care if the engine is running or not? Isn't the coil energized either way and why would it fry if the car is parked? Isn't it meant to be on for an extended period? Maybe this is why I ran a manual choke on my 3310. (BTW, I'd fuse the choke with an in-line fuse. The panel fuse is too big).

Coppertop
Jan 8th, 02, 1:36 PM
John,

Per another member (JWagner? or Fred? if I remember right)Most require the a constant velocity of air running past (i.e. running engine) that has a cooling effect on the heating element.

If I'm wrong, forgive my post, but I always like to try to wire components to corresponding systems. (Example: why wire something that is only needed to be on when to engine is running to anything but an IGN circuit?!)

John_Muha
Jan 8th, 02, 2:10 PM
I guess I learned something. Thanks Joe. As I mentioned, carburetors are not something I play with much.

Gene McGill
Jan 8th, 02, 7:00 PM
Personally, I would think the heating element is out of any air stream (intake air or cooling fan air) that might cool it. Would you not put in electric fans becuase with a cold engine the fans would be off and not cool the choke?
Also, would it be cool (pun intended http://www.chevelles.com/forum/biggrin.gif) to run the choke off the ignition if it has been converted to HEI? As far as I know, the only reason you don't want to hook it up to the coil is because #1, you create a larger drop across the resistive wiring resulting in lower voltage which could cause the choke not to fully open, and may effect ignition, #2, the resistive wire may overheat from the additional power it is disappating and #3, the voltage is low to begin with, regardless of the extra drain it would impose. I would say that if you still have the resistive wiring, it's a no-no, but HEI conversion or Block resistor ( wired to the ignition switch side of the resistor) conversion, it should be OK. Any thoughts?

[This message has been edited by Gene McGill (edited 01-08-2002).]

Dean
Jan 8th, 02, 7:49 PM
I was just thinking the same thing Gene
It makes sense that the resistive circuit is the reason why they say not to connect into the coil feed

jhow66
Jan 9th, 02, 5:58 PM
How about running it this way---get a oil pressure switch with two prongs--one wire from ing. on fuse panel--the other wire to electric choke. This way it has no power until there is oil pressure. Just put a T in where present oil pressure switch is. Works great on my 71 chevy pickup with 502 crate motor. I also used a 3 prong switch to run my electric pump. This way while I am cranking motor the pump runs (run wire from i post on solenoid--wire from ing.--wire to pump.) With motor running pump runs as long as there is oil pressure--no oil pressure no running pump.Safer this way. Sorry to be so lon winded.

Georgia69
Jan 10th, 02, 7:15 AM
I'm pretty sure Holley carbs use a vacuum source to pull air past the choke and keep it from overheating. There are two different designs...the vacuum secondary carbs use an internal vacuum source to the choke, and the double pumpers use an external vacuum hose for the same function.

------------------
Mike Newby

69 Chevelle 355/TH200-4R
97 Grand Prix GTP
64 Chevy C10 Pickup
79 Suzuki GS550

wildman704
Jan 10th, 02, 8:12 AM
Georgia69, This carb has the vacuum secondaries. Does this make any difference on where to pick up the power source for the elect choke?

------------------
Tom (Wildman704)
72 Chevelle SS454
67 Camaro Super Street
runs 10.3's @ 130 mph
01 Vette
98 Ram V10 (tow truck)

Georgia69
Jan 10th, 02, 11:17 AM
Tom,
No, it makes no difference. I ran a wire to the IGN spade terminal on the fuse box as Coppertop describes, at least until I ordered a custom engine harness that included a choke wire. Please note that if you remove the choke mechanism entirely from a #3310, or any other vacuum secondary Holley, this will leave exposed a small orifice that provided vacuum to cool the choke. You will have to plug this orifice with RTV or epoxy in order to avoid a vacuum leak.

------------------
Mike Newby

69 Chevelle 355/TH200-4R
97 Grand Prix GTP
64 Chevy C10 Pickup
79 Suzuki GS550

wildman704
Jan 10th, 02, 11:42 AM
Mike, Thanks for the info. I did not know that about the vacuum cooling.

------------------
Tom (Wildman704)
72 Chevelle SS454
67 Camaro Super Street
runs 10.3's @ 130 mph
01 Vette
98 Ram V10 (tow truck)