Cliff's Quadrajet Parts and Rebuild Kits

Quadrajet Problem Solving => Diagnose a Quadrajet carburetor problem => Topic started by: sixth_sense676 on March 30, 2013, 02:19:49 PM

Title: Ported vacuum not acting ported.
Post by: sixth_sense676 on March 30, 2013, 02:19:49 PM

Having trouble with my ported vacuum. The port is always producing vacuum for some reason. This causes obvious problems for my vacuum advance. How do I fix this/why is it doing this?

Also, when I shut off the engine hazy fumes float up out of the carb. Is this normal?

Title: Re: Ported vacuum not acting ported.
Post by: 429bbf on March 30, 2013, 09:31:41 PM

do you know what your idle rpms are ? it sounds like your idling to fast and your throttle plates are open to far causing the problem.

Title: Re: Ported vacuum not acting ported.
Post by: Cliff Ruggles on March 31, 2013, 03:19:40 AM

What is the carburetor number?

What is it being used on?

What have you done to the carburetor?


.....Cliff

Title: Re: Ported vacuum not acting ported.
Post by: sixth_sense676 on April 02, 2013, 06:31:45 PM

Carb# 17058253

9.1:1 C.R. Pontiac 350 XE262Cam

Idle @ 900RPM, though at 500rpm the port was still open.

I rebuilt the carb with a HP kit and recipe #1.

Title: Re: Ported vacuum not acting ported.
Post by: Cliff Ruggles on April 03, 2013, 05:08:59 AM

Most likely needs more idle fuel and idle bypass air.  Recipe #1 is not enough for that engine/cam combination....IMHO