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Trouble with Triple Weber Carbs and keeping an idle

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I'm reposting this in here out of the "Help Me" section in hopes to get some more responses.

So now something odd is happening with the idle. So when I start it up, I have to play with the gas for about 3 minutes until the temperature probe moves on the dash, then if I let go of the gas it'll stumble low to about 400 rpm and die.

On the other hand, if I pop the hood and manually give the throttle a little "blip" it'll go to about 850 rpm and idle great.

So I thought maybe I have to just give it a tap or two of the gas pedal to recreate the same thing. NO! It doesn't work. If I then proceed to pop the hood and "blip" it again it'll idle fine.

Also after some time driving trying to figure this out, the idle still draws to a stall and will have a hard time regulating the idle unless I manually press the throttle lever on the carbs.

-Idle at 850 rpm. It drops to about 650-700 rpm with lights, fan, and radio on.

-Idle screw down 3/32 of a turn past touching

-Mixture screws set to 1 1/4 turn out all the way across

For reference the carbs are:


36mm choke

155 Main Jets

170 Corrector Jets

55 F8 Idle Jets

F16 Emulsion tubes

On my previous tune last where I microtuned with the ColorTune Tool for the mixture I got for the turns out

#1- 1 1/4

#2- 1/1/4

#3- 3/4

#4- 1/1/4

#5- 3/4

#6- 3/4

Please HELP!



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Maybe you have some throttle bushings binding. When you do it by hand, you are putting different pressure at different points.

Also, do you have "choke" cables hooked up? If so, are they hitting the hood when closed?

Are you starving for fuel? Clogged filters/lines. My 40dcoe's required a fuel pressure regulator set at 3 lbs to avoid over-pressuring the floats - it would leak out of the chokes. If you have a FPR, it could be set too low.

Do you have a rusty/dirty gas tank or worse a perforated pick up tube? This will cause problems at higher RPM's and possibly at idle if you are running on less than a full tank. Speaking here from experience.

Do the 45's have any screens on the inlets to check? 40's dont.

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