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*C-10 simplex* · 03-28-2011, 05:10 AM

1) [(If yer broke, do you really need the secondaries?) Rhetorical question]

2) The secondaries are mechanical so stepping on the throttle past say 3/4 to the floor should open them up.

What may be happening is the air flaps (these are the metal flaps sitting flush with the top of the carb where the air cleaner base sits on, not where the carb connects to the intake), may not be opening.
These can be adjusted with a small screw located on the along the top of the carb somewhere and/or there may be a problem with a vacuum line or cannister as these flaps are vacuum controlled.

3) If the actual secondary throttle blades are not opening, there could be a problem with the choke lockout tab. But check #2 first.

P.S. In park or neutral, these secondary air flaps should not open much just revving it. Or should they?

03-28-2011, 05:10 AM	#2
C-10 simplex Account Suspended Join Date: Dec 2008 Location: indisclosed Posts: 1,515	Re: quadrajet info 1) [(If yer broke, do you really need the secondaries?) Rhetorical question] 2) The secondaries are mechanical so stepping on the throttle past say 3/4 to the floor should open them up. What may be happening is the air flaps (these are the metal flaps sitting flush with the top of the carb where the air cleaner base sits on, not where the carb connects to the intake), may not be opening. These can be adjusted with a small screw located on the along the top of the carb somewhere and/or there may be a problem with a vacuum line or cannister as these flaps are vacuum controlled. 3) If the actual secondary throttle blades are not opening, there could be a problem with the choke lockout tab. But check #2 first. P.S. In park or neutral, these secondary air flaps should not open much just revving it. Or should they? Last edited by C-10 simplex; 03-28-2011 at 05:21 AM.