Secondaris are not kickin in on the q-jet?

[uno99]

I have a 79 olds 350 in my truck with a q-jet carb. I went for a ride today and really jumped on the gas a few times which I never really do. Now I do not know much about these qjets but the secondarys are definatly not opening. I'm not sure where to start trouble shooting. Should I start looking at the LINKAGE first then check the AIR VALVE adjustment. PLEASE HELP.

[Ivan D.]

Yer secondaries are opening, trust me, it's the air valve above them that ain't - did you jump on the gas with the engine still cold? Cause there's a lockout linkage for that on the passenger side, what it does is prevent the air valve from opening while the engine is still cold - now how does it achieve that by running on only engine vacuum I ain't got no clue, but that's what it's supposed to do. Pull the vacuum line that feeds this linkage's vacuum solenoid, cap off the port on the carb's body where that line plugged in (you don't want any vacuum leaks), make sure the air valve flapper opens smoothly (by pressing on it, or turning the small lever on the side of the carb where the lockout connects to), then go for a test drive - warm up the engine good, then lay on the gas, if works fine then you had a problem with the lockout system, if it still stumbles then yer lockout was most likely fine and the problem is elsewhere.

[uno99]

Thx IVAN D. The engine was warmed up for sure. I will give it a shot 2nite after work then post up with the outcome.

[uno99]

Well I did the following posted above and nothing changed. It does not stumble it runs fines, I just don't get that initial hit when the secondaries open like I use to.

[Ivan D.]

The air-valve moves freely by hand, I take it? take the carb off and break it down, maybe there's some dirt that's clogging the secondary fuel passages?