quadrajet one day it idles good, the next day it idles bad please help!!!

[casual dreamer]

this has been the story for a while. i had this carb on my 69 chevy biscayne before, i just put it on my 68 caprice. the carb # is 29223. my friend had rebuilt it with Cliff's sr kit, he also bushed the throttle shaft. he didnt remove or replace the idle tubes, i bought a set from cliff and am ready to put them on. do you think this will solve this problem? what else should i do while i have the carb apart to make the idle smooth and dependable? my goal is to have a super smooth idle. in case it makes any difference it is on a 68 chevy 327 275 BHP, automatic trans, original points ignition. thanks!

[429bbf]

id start with the ignition. i had a lot of points do some funny things ,had to laugh ,ill bet theres a number of folks on this forum that have never seen points .if i recall it was around 75 when the started hei. anyway back to the problem. iv bought cheap and expensive points .what i found my biggest problem was the distributor shaft was loose in the bushing,and it would cause erratic idle like your talking about. do you have a different one you can try?i know you said it did the same thing on 2 differ car. but i would still not rule out the points.fwiw

[Frank400]

If you suspect your idle tubes to be clogged, the thing you can try if you don't want to remove them (I was afraid of messing with them when I first started playing seriously with Qjets but now it's a piece of cake) is to use a piece of .023" mig wire to "clean" them.

  Frank.

[Cliff Ruggles]

We consider idle tube removal and cleaning another step required for a good end result. 

I wouldn't rule out a vacuum leak someplace, or distributor issue either.  A sticking mechanical advance mechanism will cause all sorts of idle issues, and it will change every time the wind blows. 

A well worn distributor will do the same thing, as point dewell will vary some and change timing and spark, etc.....Cliff

[casual dreamer]

thanks for the replies, i sprayed some carb cleaner down the air bleed and it unclogged it. im going to pull the carb off and change the idle tubes. thanks again for the advise!

[Cliff Ruggles]

Some compressed air shot into the mixture screw holes will often dis-lodge anything that has found it's way into the idle system....Cliff