Q-Jet choke plate stuck open

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firebane

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Well that rod is connected to the spring in the device in the manifold so you need a visual way of checking that it works and you can only do that by watching it.

When the motor is cold the spring tightens which closes the choke and as it heats up the spring loosens opening the choke plate.

So record that when the truck is cold and you will have a better idea immediately.
 

Georgeb

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I found that if the choke rod contacted the sheetmetal cover it wouldn't move properly. That choke spring is not very strong. You may have the wrong rod in there. You could bend it to clear if needed. I would do the setup of the choke without the cover on and then install it once everything works. I have a book with all the info you need. I will scan it and post it later. If only I could get my hands on that thing! Would have it working in no time.
 

raylanr

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I found that if the choke rod contacted the sheetmetal cover it wouldn't move properly. That choke spring is not very strong. You may have the wrong rod in there. You could bend it to clear if needed. I would do the setup of the choke without the cover on and then install it once everything works. I have a book with all the info you need. I will scan it and post it later. If only I could get my hands on that thing! Would have it working in no time.
That would be really great George! I'm going to try to make a short video of how the rod moves and the choke spring move.

The metal piece that I move by it self is the one that was held with the zip tie, if I push on it down it will get the choke stuck open. I have to print the driver side to release it. If that make sense
 

Georgeb

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That's the high idle cam. If you pull it up with the throttle opened and then release the throttle spring pressure should hold it up and thus hold the choke closed provided the linkages and high idle screw are all set correctly.
 

Georgeb

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Here you go. The quality is a little lacking and I am not sure how to make it better. I could email it to you if needed as well. I don't have any of the special tools they mention but i didn't need them either.
 

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raylanr

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Thanks GeorgeB. Right now my other square died probably a fuel pump issue
 

MrMarty51

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One thing, to get the choke to fully close. The throttle needs to be opened fully.
Check Your cable/linkage to be sure that the plates are fully opening, with the pedal to the metal.
The reason that the zip tie was on there was to keep the fast idle cam from operating, also, the linkage rod, going to the choke pull off has been bent to keep the choke from closing. When the engine is started, the choke pull off should be adjusted so that, it will pull open the choke but, not pull it open so far that it lens out the fuel/air mix so much that the engine dies when it is cold.
Get a vacuum pump, attach it to the choke pull off, vacuum up the diaphragm, it should hold, now, with vacuum applied, slight pressure on choke plat, towards the closed position, adjust the rod, by bending it, so that the choke is open about 3/8ths of an inch open. The book gives degrees of angle but, most people have no angle gauge so I adjust the pull off to 3/8ths then, after the engine is started and running, make My final adjustments from there. Just not so far closed that the engine lopes and, not so far open that the engine dies.
Someone did`nt know any thing about adjusting the Q jet carbs and so, they jerry rigged it so that the choke would not work at all.
Just remember, before making any adjustments to the choke, be sure to full open the throttle then, close the choke plate then, release the throttle while holding the choke plate shut. By doing this, it will also set the fast idle cam, read the instructions/specs for which step of the cam the fast idle adjuster screw should be setting on.
Good luck, I think You will get it all figured out and have a great running pigumup.
 
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Georgeb

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By the way I also have the vacuum line diagrams if needed to cover the discussion regarding where all the lines run and where things connect. I could scan those in too.
 

raylanr

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By the way I also have the vacuum line diagrams if needed to cover the discussion regarding where all the lines run and where things connect. I could scan those in too.

That will be great @Georgeb!
 

raylanr

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@Georgeb, @MrMarty51 and everyone else.

When you said push the throttle fully open is like I'm flooring it correct? if so, I tried that, but the high idle will get stuck or something gets stuck and the choke plate stays open is not until I move the choke by itself that it disengaged.

If that make sense.
 

MrMarty51

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@Georgeb, @MrMarty51 and everyone else.

When you said push the throttle fully open is like I'm flooring it correct? if so, I tried that, but the high idle will get stuck or something gets stuck and the choke plate stays open is not until I move the choke by itself that it disengaged.

If that make sense.
Yes, flooring it is correct.
Try bending the choke rod that goes to the vacuum pull off, so that it is in about the middle of the slot, see if that makes a difference. I am just guessing at this but, I think with that choke rod bent right tight against the pull off, might be interfering with the operation of the choke.
Someone correct Me if I am wrong.
 

Georgeb

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Yes the linkage is messed up.
 

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