Q-Jet choke plate stuck open

[raylanr]

Its ok if the choke plate doesn't completely close! It can be open a tiny bit. The key is that when the truck is running the choke pull off opens it up with the choke. It also looks like you have a vacuum line plugged off for the choke pull off which should be hooked up as well.

You notice that on the passenger side with the rubber and screw right!
I was going to bring that up later on is bothering me that is not plug to anything. there are a lot of lines plug like that on the truck.

I don't know where that connects to, but there is a line plug also from the air filter bowl that I don't know where i plugs in.

 

[firebane]

You notice that on the passenger side with the rubber and screw right!
I was going to bring that up later on is bothering me that is not plug to anything. there are a lot of lines plug like that on the truck.

I don't know where that connects to, but there is a line plug also from the air filter bowl that I don't know where i plugs in.

There is usually a spot on the carb for choke pull offs. Its usually pretty close to the choke pull off itself but if you can't find one plug it into a spot and see if you get any change.

Here is a link to the manual for carb perhaps it will help: http://www.gmcmi.com/wp-content/uploads/2014/05/Quadrajet_78-Service-Manual.pdf

 

[raylanr]

There is usually a spot on the carb for choke pull offs. Its usually pretty close to the choke pull off itself but if you can't find one plug it into a spot and see if you get any change.

Here is a link to the manual for carb perhaps it will help: http://www.gmcmi.com/wp-content/uploads/2014/05/Quadrajet_78-Service-Manual.pdf

there is one line plug in to the choke pull off on these pic the one that is plug with the bolt is lower and closer to the choke relatively. I don't know if it goes up to the filter bowl maybe or is the one that actually needs to be plug to the choke pull off. the one with the T split I can't remember where does it goes.

 

[firebane]

Ok so you have vacuum to your choke pull off so not sure what that other line is for. If you take the vacuum line off the carb and push the lever for the choke pull off down and block the end of the rubber hose with your thumb does the lever stay retracted?

 

[Quadrajet Power]

The zip tie may have been there to keep it open because it wasn't adjusted correctly. When engine is warm, it should be all the way open on its own.

 

[Don5]

In the pic with the T split, I have that port plugged with rubber cap. I also do not have a auto transmission either. In the other pic, my vacuum advance from the distributor is hooked up to that port.

I think, correction I know the zip tie is a band aid. I don't think the choke is operating right and the PO did what he could to fix, ahem-cough cough, it.

On those divorced style chokes there are 3 rods that can be used. I would replace the choke spring located in the metal box on the intake right next to the carb. I bet it is broke and that is why the PO used the zip tie. It might just be weak too. Those rods can be adjusted with a pair of needle nose pliers. However I don't recommend that route. See if you can get a couple of the rods if the spring is not broken. I hope this helps.

^I bet Qjet nailed it in his last post BTW.

 

[raylanr]

I finally got an hour free and was able to soaked the carburetor on carb cleaner. Cut of the zip tie and got things moving.
I didn't succeeded on getting her to start though.
This little video is of how she sounds...

 

[raylanr]

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[Georgeb]

it's hard to tell from the pics but is your choke spring connected to the correct position? If i get a chance I will take some video of my 78 choke operation. same setup works great!

 

[Don5]

^Nice catch George! I didn't notice it but you are right. It should be hooked up where the outlined arrow is pointing to. I couldn't see it due to the pics so I went back and looked closely. You can see it in one of the pics on the first page.

 

[MadOgre]

Yes it is supposed to be hooked up here :

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The linkage goes in from the inside and then has a little cotter pin/stop on the outside

 

[raylanr]

I just took this picture I think is connected to the right place.

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I just think the rod is bend or it got bend at one point.
@Georgeb did you see this post?

I straightened the rod on the choke plate. and that is how the rod looks on the choke pull.

 

[firebane]

Well the pull off spring looks better. Have you tested the pull off to see if it holds vacuum?

Have someone video the carb when you start it as well so you can see what is happening.

 

[raylanr]

I made a video of the parts moving but I didn't thought about having someone video while I try to start it.

Did you notice the bend rod for the pull choke, is that right?

 

[raylanr]

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