rst08tierney

How bigs the carb?

Did it work on the car before?

What Brand?

SuperHoss

Before I let the car set up for three weeks it would run fine, after I came back the car would not idle.

I have a 4150 series double pumper Holley that is 650cfm and has 4 corned idle circuits...as for the distributor; it is a 71000 series Accel Billetproof breakerless distributor for a small block Ford.

By not idling I mean that the engine has to be around 1100+ rpms in order for it to continue running, if the engine falls below that rpms it will shut off (it does not matter if the engine is hot or cold).

67t5ponycoupe

Do you have another carb you could bolt on to see if it makes a difference?

Iskwezm

have you tried using a vacume guage to check if its still leaking thought a port or gaskets?

kalli

that's a tell tale sympom for a huge vacuum leak. I had the very same. As mentioned before. I bought a complete engine that was taken out of a car. at the intakes back directly under the carb was a pickup for brake servo etc that was not plugged that I never saw. It would rev and keep easy up at 2000 but as soon as I dropped the throttle under 1500 it would just stall. There was a hissing sound that eventually gave it away, but it's more for a trained ear.
Check again the carburetor and the intake. yes. over that again. I'm 99% sure you forgot to plug something. if everything is plugged then one of the big hoses (PCV, servo) might leak or the servo or PCV is open at all times. so as said if all is plugged make sure to disconnect and block all vacuum hoses that you have attached to carb and intake. Usually I'd say use a brake cleaner or something like that during engine is running and spray around intake and carb when it's running to see if rpm drops or rises when you spray at a certain spot, but in your case (like mine) it sounds like a huge leak.

SuperHoss

All of the unused holes on the intake are actually plugged (as was suggested, I checked them today) but the PCV or its hose may be the source of the problem...my neighbor has a vacuum gauge and I will be able to borrow it in hopes of finding the problem. The good thing is that there is only one hose on my engine that is not related to water flow...the one for the PCV.

The carburetor is fine, when I took it to get rebuilt the man said that it was already in good shape aside from being a little out of adjustment...just the same, I requested that he disassemble and clean it anyway. The only spare I have is a 20 year old 750 cfm double pumper that is in dire need of rebuilding...so I do not have any others that I can use.

kalli

remove the hose from PCV and block it where the PCV was. if that works for you then you know where the problem is. obviously the hose has to be tight and not leaking.
what intake is it exactly?

I usually work vacuum gauges but if the car cannot idle I wouldn't know how the gauge would help.
I still think it's a massive leak and if the PCV is stuck fully open, then yes that will cause that

JMD

I have seen a car run much the way you describe when a Duraspark box was failing, and again when the valve timing had slipped a tooth.

SuperHoss

The intake is an RPM Airgap

kalli

any luck with blocking the hose going to PCV?