Vacuum leak at idle

[Mike X]

Carb No. 17054931.  Won't idle.  Sounds like it's sucking air.  Carb ran fine except for stuck needle and seat, so I cleaned it and replaced the needle and seat.  A close examination of the bowl gasket shows deep imprints from the top of the bowl, so it doesn't appear to be leaking there.  It leaks vacuum so badly I can't keep it running except at wide open throttle.  I've had it apart again and double checked for correct gaskets and I can't see anything wrong.  What do I do now? 

[comp]

have you checked the base gasket ?

[omaha]

You must have a big vacuum leak somewhere. Do you have power brakes. Maybe the power brake booster is leaking.
Need to try the usual tricks for finding vacuum leaks.

[Cliff Ruggles]

Were any of the gaskets replaced during the repairs?  Sounds like one of them is not correct for the carburetor, or you have missed something somplace when hooking up all the hoses, etc.....Cliff

[Marx3]

I once had a sudden vacuum leak, and I just could not find it. After spraying and spraying with diesel-start, I finally found it at the base gasket, just underneath the vacuum port for the brakes.
It was leaking in an area of about 0.07" wide at the gasket. Very hard to find!