1981 q-jet secondaries
Thread Starter
Cruising
Joined: Jun 2008
Posts: 13
Likes: 0
1981 q-jet secondaries
I have a 1981 with the stock rochester quadrajet and the secondaries are only opening about 1/16 of the way at wot. Where these carbs set up this way or is something wrong? any ideas on how to correct this problem would be appreciated. thanks
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Are you talking about the air valve? Are you trying to get them to open in your driveway while you're watching them? If so, the secondaries probably are opening all the way and the air valve is doing exactly what it is supposed to do. The only convenient way to see the air valve in action is to run the car under load at WOT on a chassis dyno with the air cleaner lid off.
BigBlockk
Later.....
BigBlockk
Later.....
Thread Starter
Cruising
Joined: Jun 2008
Posts: 13
Likes: 0
yep sitting still in the shop running the throttle by hand on the carb. the air valve and the secondaries are both staying closed when i rev it up i flipped the air valves open and the secondaries were only opening 1/16 as well as the air valves
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
With the engine off and the air valve open so you can see inside you should be able to get the secondarys to open wide.Check to make sure the secondary lockout is not engaged.The choke controls it.If you cant get the secondarys to open then you have a problem.
Le Mans Master
Joined: Jan 2007
Posts: 5,485
Likes: 7
From: Peekskill NY
With the engine off and warmed up, push the throttle cable to the WOT position. There's a metal tab called the 'tang" on the primary which engages the secondary pushrod. The tang is soft metal and can be bent to adjust until the secondary opens up completely. Do it a little bit at a time until fully open. When I got my 70, I had no secondaries at all, and Eddie70 helped me out and now they open fully. MAJOR difference at WOT now.
Good luck, Glenn
Good luck, Glenn
Drifting
Joined: Sep 2004
Posts: 1,959
Likes: 1
From: North Bend Ohio
Has this carburetor been apart recently? If the linkage is correct (GD70's post) and the secondary lock out isn't mis adjusted (DWncchs' post) there may be a gasket issue. I've seen the secondaries get bound up on sloppy gaskets.
BigBlockk
Later.....
BigBlockk
Later.....
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