Idle problems

I've been playing with the DUI and my carb and now i'm having idle troubles. Car starts every time but the rpm's shoot up on start up, then they settle down. But then they shoot back up again. This repeats a couple times then the car dies.

Any thoughts???

Need help quick

Float level? Perhaps it's stuck?

how would i go about checking that?
Thanks

What do you mean by playing with the carb. Did you take it apart? Sometimes if a float is stuck if you tap the carb at the intake the needle with come loose.

The float is a bulb inside the fuel reservoir. The fuel reservoir is the large area to the front of your carb if you have a 1100. If you have a Carter, it is the well-shaped area to the front of the carb. You have to take the top of the carb off to look into it. Sometimes you can just take the top of the fuel reservoir.

You can work the float with your finger or give it puff of compressed air at the needle valve seat and the float hinges. Use one of those cans of compressed air for cleaning computers, NOT your garage compressor. Also, do not work it very hard because it is only activated by the level of fluid in the carb and you can push it out of adjustment (although you probably won't).

At what rpm is it surging? It could be that your rpm's are up in the bottom range of the centrifugal advance and it is leading to an unstable idle. If you are using manifold vac for the distributor, the same thing can happen if the engine has low vacuum or the vac cannister has a operating range that is too high for the engine idle vacuum. The vac advance will be unstable if the engine vac does not fully advance the vacuum advance.
Doug

Are you guy with moving timing mark?
And possible balancer issue?

That actually makes sense. I didn't know what to do with the idea of the moving mark on the ring. Slipped, yes; actually moving, no. Use a white pen and make a mark on the side of the rubber damper mount and see if that one wanders. Bet not.

im using manifold vac and it surges up to about 1500 to 1600 rmp then drops to about 800 and repeats a few times then dies... no balancer issues either...

Well, shoot. That's all I got.

took the carb apart a replaced a bad power valve... starts up with no surging of the idle but still wants to shut off until it warms up... but now when i push in the clutch and role up to the stop light as the rpm's drop, they just keep going until the car turns off... now i think im looking for a vac leak becuase my brakes were very hard to push... its always somethin...

what should i set the float level at, btw? If i have to adjust it, that is... its an autolite 2100, 1.14

Well, I got pissed and decided to just rebuild the whole dang carb today. Get everything set back up, prayed a little bit and it started right up and runs the best it ever has. idles amazing. almost sounds a little like my brothers corvette Z06. hahaha

Sounds like you kinda scared it into behaving.

hahaha! my thoughts exactly! soon it will get comfortable and start giving me attitude again though, I am sure. :roll: LOL. But for now, it works

it was that prayin that you done that got it runnin right

agreed !!!
oh and by the way, before rebuilding the whole thing i took it apart and replaced a bad power valve, i thought that would clear up my issues right away but it didnt. We couldn't figure out what else was wrong after resetting the float level playing with the jets and everything else. So then the rebuild and now everything is fine

Little praying yeah It helps