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66 coupe fast-idle failure

  • Thread starter Thread starter dude43
  • Start date Start date Mar 1, 2009
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dude43

New Member
Oct 28, 2007
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Mar 1, 2009
#1
  • Mar 1, 2009
  • #1
I recently switched the manual choke on my 66 coupe to automatic using a holley conversion kit. My fast idle however doesn't work, i know that the fast-idle screw should be just slightly resting on the first step of the fast-idle cam but i dont know how to adjust the fast-idle screw while it is all put together on the carb. because i cant see the end of the screw or cam and cant get a screwdriver in their even an offset. thanks for the help
 

jcode68

Active Member
Jul 15, 2003
892
1
29
Massachussetts
Mar 1, 2009
#2
  • Mar 1, 2009
  • #2
The fast idle screw is really tough to get too, but can be done without removal of the carb or choke. You need to move the accelerator linkage all the way forward and hold it in place with something. Then, from the passenger side, underneath the choke housing, you will be able to see and access the fast idle screw. You can either use a small wrench (I think it's 1/4") or a small philips head screwdriver (if you have one bent in an "L" shape, it will be easier). Having small hands is also helpful ;-) You should find instructions and pictures in the Holley manual for your carb.
 
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dude43

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Oct 28, 2007
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Mar 1, 2009
#3
  • Mar 1, 2009
  • #3
thanks deff easier to reach now. so the screw should just rest on the cam right?
 

jcode68

Active Member
Jul 15, 2003
892
1
29
Massachussetts
Mar 1, 2009
#4
  • Mar 1, 2009
  • #4
dude43 said:
thanks deff easier to reach now. so the screw should just rest on the cam right?
Click to expand...

Yes, that is how I recall it.
 

BarnStang

Founding Member
Mar 2, 2001
1,260
3
39
Hagerstown, MD
Mar 2, 2009
#5
  • Mar 2, 2009
  • #5
When the choke is completely OFF, you need some small amount of space to adjust the curb idle. I have run into a few cars that could not adjust the curb idle lower cause the fast idle screw was hitting the first step and stopping it from dropping lower.
 
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