Can’t get the Barracuda to idle down

[Matt13]

Well, the car starts and runs well now after going through just about everything. Only problem I'm still having is even after running for 20-30mins, the car won't idle down. It keeps the same fast idle from at start. Everything is dialed in nicely and she starts rather easily compared to the difficult starts it used to have. What am I missing? TIA

[70 Challenger Lover]

There is linkage on the side of the carb that kicks up the idle speed while it warms up. Sounds like it's sticking and not dropping free as the choke blade opens up.

[Brads70]

     and/or Vacuum leak? 

[Chryco Psycho]

 
What type of carb , heat activated choke or electric or does it even have a choke system ?
Any pix ?Could also be  a vacuum leak /

[7212Mopar]

It also could be your throttle cable sticking. Only clamp down at the metal sleeve of the cable. Many after market cables are too short or too long or sleeve at the wrong spot. Call Dave at Roseville. They have the correct cable.

[anlauto]

...vacuum leak was my first thought as well 

[Matt13]

Checked for vacuum leaks first; none. Carb is a brand new Holley.

[Brads70]

Not common, but look down the open throttle blades and make sure it's not hanging up on the intake or gasket?

[anlauto]

You got it on upside down....duh...

[DeathProofCuda]

What rpm is the engine running at?  If you have an auto trans, is that in park or in gear?  Are you saying that the rpm doesn't change at all when you back out the idle adjustment screw?

Have you verified whether or not the carb linkage is running on the fast idle cam?  From your pics its looks like the choke is pretty much wide open, so the fast idle cam should be dropping out of place unless your choke linkage is hung up for some reason.

Can you send a pic of the choke linkage side of the carb?

[7212Mopar]

Looks like you are clamping the sheath part of your throttle cable and not the metal sleeve. May need to double up your return spring?

[73_Cuda_4_Me]

 

I don't believe the kickdown rod should have 2 bolts going through it... the main pin bolt toward rear, yes, but the one in the front seems like it would bind  with the main pin when throttle is applied or let off...???

[Matt13]

Well, the carb is an exact modern replacement for the 20 yr old carb that was on it when I bought it. I retained all the original linkage. I do think I will try to replace the kickdown cable next. Perhaps it is binding up under the sheath as suggested?

[73_Cuda_4_Me]

The clamped cable sheath is the throttle cable attached to the gas pedal. On my 73, the clamp is around the metal part of outer sheath. The kickdown rod is the one with the long slot in it.

First thing I'd do to check idle is to disconnect the throttle cable and the kickdown, just have a spring pulling throttle bracket on carb to idle position. If you can't adjust idle down then, it's something in the carb linkage or mounting.

You should be able to pull throttle cable all the way out (gas pedal fully up), and have it just long enough to hook onto throttle linkage at idle. Adjust the sheath clamp to set it so there is just a little play at that idle setting.

Then loop kickdown over throttle post mount, and with engine off, push throttle all the way open, and make sure that kickdown is just ending it's travel down on transmission just as throttle is hitting wide open (use single nut clamping the slotted rod that goes down to tranny to adjust it.

[Matt13]

Excellent. I will do that. Thanks!