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Old 08-21-2013, 06:16 PM   #1
slow-1
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QuadraJet Secondary Linkage

Since I had my Q-Jet rebuilt by a buddy who has done many of them successfully for me in the past, I noticed the secondary's weren't opening (not a problem while I was taking it easy on it after the engine rebuild).

So I decided today to see if I could figure it out.

I checked to make sure the choke was opening fully allowing the secondary air valve (flapper) to open, it is working correctly and I can easily open the air valve with my finger.

I then looked to see if the secondary butterflies were opening at WOT...they are not, in fact they barely move at all.

Is the linkage assembled wrong?

Closed throttle:



WOT:



As you can see, the secondary butterflies hardly move.

I read that to adjust the amount the secondary's open you bend the tab on the primary shaft, but the tap seems to be out of position, I don't see a way to bend it enough and it still work.

Any insight is appreciated.
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Old 08-21-2013, 06:24 PM   #2
slow-1
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Re: QuadraJet Secondary Linkage

Here is a pic of the primary shaft tabs, the one on the left pushes the one on the right to open the secondary's. They seem too far apart.

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Old 08-21-2013, 06:27 PM   #3
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Re: QuadraJet Secondary Linkage

Oh...and y'all don't be jealous of my hand made trans kick-down cable bracket.
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Old 08-21-2013, 06:44 PM   #4
Lee H
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Re: QuadraJet Secondary Linkage

The secondaries will not open unless under a load on a running engine. You can even get them to open in park or neutral at WOT.
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Old 08-21-2013, 07:08 PM   #5
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Re: QuadraJet Secondary Linkage

Quote:
Originally Posted by lee h View Post
the secondaries will not open unless under a load on a running engine. You can even get them to open in park or neutral at wot.
^2
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Old 08-21-2013, 07:35 PM   #6
JimKshortstep4x4
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Re: QuadraJet Secondary Linkage

The primary tabs look ok but your primary section is not opening up far enough. The secondary throttle plates are opened by the levers and connecting rod but the movement on the secondaries does not start until the primary side is approximately 3/4 opened. Your picture shows that the primary side is not opened all of the way. If you can get the primary side to open all of the way the secondary plates will probably be opened all of the way. I would suggest checking your cables as they may prevent the throttle from opening all of the way.

Jim
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Old 08-21-2013, 07:48 PM   #7
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Re: QuadraJet Secondary Linkage

The secondary air flaps open by vacuum as the engine demands more air. The throttle plate butterfly's open mechanically beyond ~60% peddle input.

Take a picture of the other side. Sometimes the choke linkage is installed incorrectly and the little hoodus that holds the secondary's closed during choke operation gets jammed in the "on" position. Most likely this is your problem. Simple mistake, simple fix.
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Old 08-21-2013, 08:40 PM   #8
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Re: QuadraJet Secondary Linkage

Quote:
Originally Posted by mmiddle View Post
The secondary air flaps open by vacuum as the engine demands more air. The throttle plate butterfly's open mechanically beyond ~60% peddle input.

Take a picture of the other side. Sometimes the choke linkage is installed incorrectly and the little hoodus that holds the secondary's closed during choke operation gets jammed in the "on" position. Most likely this is your problem. Simple mistake, simple fix.
Lots of people miss this little lock-out lever!Sometimes it gets re-installed flipped over too.
Mike.
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Old 08-21-2013, 08:56 PM   #9
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Re: QuadraJet Secondary Linkage

Yep...there are things on the right side that are loose that probably shouldn't be.

When I move that bottom one out of the way of the pin in the secondary shaft I can move all the way to WOT and the secondary butterflies open as they should...so what's not right?





The piece that is rotated up in the second pic along with the piece behind it are both spinning free.
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Old 08-21-2013, 09:04 PM   #10
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Re: QuadraJet Secondary Linkage

Quote:
Originally Posted by Lee H View Post
The secondaries will not open unless under a load on a running engine. You can even get them to open in park or neutral at WOT.
Sure they will...you just have to have the stones to hold the throttle wide open long enough for it to happen...and a check book to rebuild the motor when it grenades.
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Old 08-21-2013, 09:15 PM   #11
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Re: QuadraJet Secondary Linkage

Quote:
Originally Posted by slow-1 View Post
Yep...there are things on the right side that are loose that probably shouldn't be.

When I move that bottom one out of the way of the pin in the secondary shaft I can move all the way to WOT and the secondary butterflies open as they should...so what's not right?





The piece that is rotated up in the second pic along with the piece behind it are both spinning free.
Yep,that's your problem!
You'll have to remove the whole choke assembly and re-install that lever in the correct position.This is a tricky operation,so you might want to find a break-down parts drawing for a quad using the choke stove.
Mike.
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Old 08-21-2013, 09:29 PM   #12
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Re: QuadraJet Secondary Linkage

I will drive it over to my buddy and let him do it...and I will pay attention so I can recognize it myself next time.

Thanks for the help!
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Old 08-21-2013, 09:55 PM   #13
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Re: QuadraJet Secondary Linkage

When I do one for my own use, I round-file that. I know not hammer a cold motor. You don't have to have that, but if you ever let an idiot drive your truck... well, just don't let an idiot drive your truck
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Old 08-21-2013, 09:59 PM   #14
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Re: QuadraJet Secondary Linkage

Why are you missing the bolt/screw that goes here?
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Old 08-21-2013, 10:03 PM   #15
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Re: QuadraJet Secondary Linkage

Take some follow up pics when you get it set up right!
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Old 08-21-2013, 10:09 PM   #16
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Re: QuadraJet Secondary Linkage

Quote:
Originally Posted by mmiddle View Post
Why are you missing the bolt/screw that goes here?
That's a good question...I will point that out to my buddy as well.
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My first vehicle (1983)
Original 350 (3 rebuilds)
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Old 08-22-2013, 06:05 PM   #17
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Re: QuadraJet Secondary Linkage

Quote:
Originally Posted by mmiddle View Post
When I do one for my own use, I round-file that. I know not hammer a cold motor. You don't have to have that, but if you ever let an idiot drive your truck... well, just don't let an idiot drive your truck
My buddy is not available for a few days so I just took off the two loose pieces that were stopping the secondaries from opening...runs like a SCALDED DAWG now. I will keep any idiots from behind the wheel.

Thanks for the help.
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Original 350 (3 rebuilds)
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