JJ

when my accelerator pedal is pressed all the way down, the level for the primaries opens far enough that it causes the level for the secondaries to get stuck open. That little metal connector between them gets jammed just enough that it cannot go back. The connecting piece of metal has what appears to be a little coter key in one end so I was wondering if these come in different sizes/lengths and this would solve my problem, or if it needs to be worked out with the accelerator cable (this is a past tpi car with everything intact accelerator cable wise. thanks for dealing with my st

Jester

You should have AT LEAST one throttle return spring on it...I personally have 2, one for the primaries one for the secondaries. They're like 3 bux at any parts store...

------------------
"American made baby. 100% American iron. The muscle among the masses. My hero. Yep, you can take your ergonomically designed, space age, computer controlled, 4 door, cup holding map lighted split double wishbone split fold down retractable cargo covered moon roof piece of transportation and keep it. For I have felt the thunder. And I know the difference!"
Jesters's Page of Sick Pleasure
Florida Thirdgenners Message Board
ICON Motorsports

JJ

I do have one, when it gets to the point I am talking about, it is really hard to come back (I'm not sure 5 springs would pull it back). I will put another spring on and see if that helps. Thanks for the suggestion . . . Jeff

Damon

JJ- that's a dangerous condition. Make sure the throttle linkage is adjsuted properly. Engine off, open the throttle FULLY by hand. Now open the secondary air doors by had at the same time. Look down the secondary throttle bores and see of the throttle plates are opened any MORE than 90*. They should be 90 exactly. If they go more than a few degrees over 90 the air rushing though them will try to keep them OPEN, instead of helping to close them (as they were designed to do). Also, when you close the throttle the primary linkage has a catch in it that actually PULLS the secondary throttle linkage closed (at least most of the way).

Also check the geomentry of the secondary throttle "push rod" that comes back from the primaries. It SHOULD work like this: when the primaries get about 1/2 way open they will begin pushing on the secondary "push rod". The top tip of this pushrod will first push on the outer TIP of the secondary throttle arm and open the secondary throttle plates the first few degrees. Then, the BOTTOM end of the secondary pushrod will reach the end of its travel in a small elongated hole, much closer to the secondary throttle shaft. At that point the secondaries will open very quickly, so that the secondary throttles reach full 90* opening at the same time as the primaries. If this is NOT how yours is working you might need to figure out why and fix it- it's just a mechanicial linkage and the "push rod" can be bent (CAREFULLY!) to make adjustments until everything IS working correctly..

Assuming that all checks out right but you still have the problem you are down to one of two things- the linkage is binding, the throttle shaft bushings are totally shot, or your trottle cable is binding against something somewhere. Binding secondary linkage should not happen on the Qjet unless someone has fiddled with it. Worn out secondary bushings are much more common. But the most common problem of all is PRIMARY throttle shaft bearing wear. If your stock throttle return spring runs off the bottom of the primary throttle arm BACKWARDS to the same bracket that holds the throttle cable and trans kickdown cable this is a VERY LIKELY scenario. You have the pressure of the return spring AND the pressure of you pushing on the gas pedal BOTH trying to pull the primary throttle shaft towards the rear of the carb- quickly wearing out the primary throttle shaft bearings. THis allows a nasty "wedging" effect at WOT, and a stuck throttle. THere is no way you can fix these bushings yourself at home. Binding throttle cable is just a matter of using your eyeballs and looking at what it comes near from idle to WOT.




------------------
94 Firebird Formula M6- No options but Z rated tires. No mods over $10. 13.5@105.
79 Malibu "beater" w/junkyard 400 SBC, tweaked QJet 4bbl, finally a decent set of heads, a few other tricks. A maddening 13.000001 @ 108 on the motor with little traction. No nitrous runs with the new heads yet.
Grandma's old 78 Malibu (33K miles!) soon to have the powertrain from the 79 put in it.

"One of the last remaining QJet tuners on Planet Earth!"

Dan Pritchett

Alright, I have an 82 firebird 305, I just got and put a rebuilt Rochester Quadrajet on. The linkage is so tight that it clicks and idled at 4000 reps. Is that adjustable or ****ed? I been thinking about just getting a new edelbrock b/c I did a new engine 3k miles ago but if I can make this one work to the end of the year it would be ideal