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 Q Jet Secondary 
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Joined: Fri Feb 08, 2013 2:37 pm
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frank350 wrote:
Yes, I have a car linkage, not a truck linkage. Yes I did the slot. Tuner, I have to ask, is the third picture "full throttle" ? I'm asking because I'll be honest, I was trying to achieve exactly 90 degrees on the secondary.

Frank.


Yes, the third picture is full throttle. However, the camera angle, a little behind the center of the shaft, makes the throttle blade appear more vertical than it should actually be at WOT. The WOT position of the secondary throttle blade should be less than 90 degrees. The edge of the throttle blade should stop directly under the vertical baffle inserted in the body, so the blade angle will be less than 90 degrees, about 83-85 degrees.

Adjustment requires bending several things, the angle of the link (wire), the small tang attached to the primary throttle shaft, the large tang that the small tang pushes against on the lever (with the hole for the link) floating on the primary throttle shaft, and sometimes, the tang on the top of the secondary lever needs a little tilt forward, but not usually.

The conundrum of the long lever can be overcome by drilling a hole in the middle of the lever near the location of the hole in the shorter lever. Refer to cat herder's picture.


Fri Aug 28, 2015 12:58 pm
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Joined: Mon Dec 29, 2014 1:26 am
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Image


Since each adjustment affects all the others, is there a 'correct' order to make changes to minimize rebending stuff you just did?

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Fri Aug 28, 2015 3:23 pm
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Joined: Tue May 06, 2014 5:34 pm
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cat herder wrote:
Image


Since each adjustment affects all the others, is there a 'correct' order to make changes to minimize rebending stuff you just did?


That's exactly what I'd like to know, if there is a better order in which to do these adjustments.


Fri Aug 28, 2015 4:02 pm
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Sometimes this is over quick and sometimes I assemble and disassemble this a few more than a bajillion times before it's done. First, modify the secondary lever (and primary lever, drill new hole if needed), file the slot and install the pin in the secondary lever. Then, assemble it and adjust the angle of the bend at the rear of the pushrod wire link so the progression of contact with the secondary lever is correct, tip first, then pin, then end of slot, look at the attached pictures. Because the slot is longer than original, the secondary probably only opens about 50% or so. Then, adjust the lower tang on the floating lever on the primary (bend the tang up, closer to the upper lever with the pushrod hole, close up the angle between the tang and lever) so the secondary reaches the desired position at 85 or so degrees with the upper edge of the butterfly under the baffle plate insert in the main body.

If the angle of the (wire) pushrod was adjusted for correct progression on the secondary lever, the closing function was probably affected. If this is so, adjust the tang (the one fixed, solid mounted) on the throttle shaft for safe closure action and then readdress the opening action of the secondary. In this situation, adjusting the primary tang (for closing) requires re-examination of the opening action, probably adjusting (bending) the large lower tang on the floating lever.


Fri Aug 28, 2015 5:04 pm
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Joined: Mon Dec 29, 2014 1:26 am
Posts: 433
Cut the forward bend of the secondary rod off, then use this clip from the early Qjets. Makes it so much easier, the rod can be removed without disassembling any of the parts on the secondary shaft.
http://quadrajetparts.com/retainer-clip ... p-284.html

Also sold as a new rod with the clip included: http://quadrajetparts.com/secondary-throttle-p-312.html

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Fri Aug 28, 2015 5:45 pm
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Joined: Tue May 06, 2014 5:34 pm
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I'm wondering about the purpose of the .024" holes in the large tubes that feed the cap jet. Am I right guessing that as the well empties upon acceleration, it becomes progressively leaner as the level reaches the .024" holes because it introduces air thru those holes ?


Mon Dec 05, 2016 10:14 pm
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Joined: Wed Oct 23, 2013 8:01 am
Posts: 113
That would be my guess.


Tue Dec 06, 2016 9:29 am
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