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Help on adjusting Automatic Choke

  • Thread starter Thread starter estevaf
  • Start date Start date Jan 3, 2009

estevaf

Founding Member
Jul 2, 2001
194
0
0
São Paulo, BRAZIL
Jan 3, 2009
#1
  • Jan 3, 2009
  • #1
Hi, Guys.

I have installed a brand new Carb (Holley 5200 2V) that I got from e-bay.

It is working beautifully but I am having some difficulties trying to adjust the automatic choke (it is electrically assisted).
I am not sure if this adjustment is even needed.

The problem is that the choke plates seems to be opening too fast. Due to that, the car fails to keep runing because the engine is still not at the right temperature.

After some testes, I realized that I had to adjust the fast idle screw, which I did.
But if I blip on the throtle soon enough, then I loose fast idle and the engine stops (unless I stay in the car controlling the idle).

One of the tests I did was going to the engine compartiment and closing the choke plates a little bit. Then engine runs nicelly when it is not warmed up, even with the fast idle not active.

Anyone out there knows how to easily adjust the automatic choke so that the choke would take a bit longer to open?

Thanks!
 

welder4956

20+ Year Stangneter
Nov 28, 2003
230
95
38
Birmingham, AL
Jan 3, 2009
#2
  • Jan 3, 2009
  • #2
I hooked mine up to a wire from the alternator that supplies 12V when the car is running. I'll have to look to see which terminal it was.

The time to open is controlled by loosening the 3 screws on the side of the choke spring housing and rotating it. With the engine cold, loosen the 3 screws and rotate the housing until it just begins to open, then rotate it the other way until the choke is closed, then rotate an additional 1.5 notches and tighten the 3 screws.

Info on adjusting the fast idle cam can be found here:

Holley Performance Products Frequently Asked Questions
 

estevaf

Founding Member
Jul 2, 2001
194
0
0
São Paulo, BRAZIL
Jan 4, 2009
#3
  • Jan 4, 2009
  • #3
Hi,
Thanks for the info.
I have managed to connect the electric connector and also do adjust it.

I will have to do some tests now to make sure that I have the best config for the automatic choke.

Thanks!
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
3
58
NE Ohio
Jan 5, 2009
#4
  • Jan 5, 2009
  • #4
welder4956 said:
I hooked mine up to a wire from the alternator that supplies 12V when the car is running. I'll have to look to see which terminal it was.
Click to expand...

Sort of but not really.

IIRC power for the electric choke comes from one of the stator windings which will not give the full 12 (or 14.5) volt rms.

Also IIRC, powering an apparatus other than the choke from that terminal will cause problems like a buzzing in relays.

So the electric choke cant be powered by system voltage.

That is, IIRC. Which I may not.
 

Steel Steeds

New Member
Aug 31, 2005
234
1
0
Portland, OR
Jan 6, 2009
#5
  • Jan 6, 2009
  • #5
The alternator choke wire on my '78 only puts out 8 volts. I had to run a different wire to hook up my Holley's choke.
 
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