wont return to idle - webers

[mini64]

Any ideas on why my car wont return to idle(stays around 2500), or when it does it takes 10 or so seconds? There is slack in my throttle cable and the throttle butterfly mechanism goes back to hit the stop. I'm thinking maybe my distributor mechanical advance is acting up (no vacuum advance)? Or a loose butterfly? I thought about the carb to inlet gaskets may be leaking, but then why does it not return to idle sometimes, while other times it does but takes forever?

[rgh0]

Normally this problem is due to the first progression hole being partially exposed by the butterfly postion at idle and additional fuel and air being sucked through here.

cheers
Rohan

[carrierdave]

I had the same problem recently. I checked the float heights and they were way out. Engine runs like a dream now.

[Paul Chapman]

I also had similar issues of this sort which I solved by replacing the float needle valves which were both well worn and then adjusting the floats to the correct Weber settings, the idle speed now remains steady and quickly returns to the set point. Hope this helps.

[mini64]

there was some silicone remnants left on the o-ring holders from a previous install. I didnt do a good job cleaning them off. I bet this is the problem cause all I did was pull the carbs, then put them back on. If this isnt the answer I'll reply back with what I found.