New truck, trying to understand its molestation - carb/intake

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Gene King

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Hello. I bought an 86 Sierra 1500 with a 305 and a quadrajet just this past weekend and was investigating an automatic choke problem it has when I noticed the carb only has the front 2 bolts holding it down and the other the 2 rear holes don't line up to the intake. It is miserably cold outside so I was wondering what you guys could discern with this little info. It has an air pump and emissions equipment so I kind of doubt somebody tried to hotrod it, although someone did put chrome valve covers on it.
I couldn't find a useful photo angle with all that emissions crap on it but I attached a photo nonetheless.

PS. The goofy throttle return spring was held on with twist ties from a bag of bread, thought you guys might get a kick out of that.

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GXPWeasel

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Welcome, from Kansas.
Not sure of your question, and I probably wouldn't be of much help either. I have the same engine / carb combo, but I'm in the process of rebuilding, and getting rid of a lot of the crap that's there from the factory.
 

CorvairGeek

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Is that mixture control solenoid the wrong color for the truck, i.e. a car version vs. the rich/lean only version for a truck? I could be wrong being this is an '86.
 

Gene King

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Hello, and oop I missed my question trying to be brief. Looking for speculation on what's probably going on here. I read they made different bolt pattern spread bore intakes but in my dream scenario I was hoping someone could tell me there's a square bore intake under there from that info of the rear quadrajet bolts not lining up because I have a rebuilt holley on the shelf perfect for this lol. If it's some kind of weird pattern spread bore intake under there though I'll be sort of SOL although it does run. If it were a pleasant day I'd just see for myself taking the carb off but you guys see all the vacuum connections, and in 20 degree weather thought maybe I'd try here first.

@CorvairGeek I just learned that electric solenoid setup existed on carbs yesterday, kinda novel thing eh.
That would be interesting, I know the wires connecting to it have been hacked with butt connectors.
 
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Vbb199

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Welcome from nc.
Thats ALOT of vacuum hoses. Emissions i presume?
 

Ricko1966

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I need a couple more pics. Show where the bolt holes don't line up and an overhead of the whole top of the carb.
Hello, and oop I missed my question trying to be brief. Looking for speculation on what's probably going on here. I read they made different bolt pattern spread bore intakes but in my dream scenario I was hoping someone could tell me there's a square bore intake under there from that info of the rear quadrajet bolts not lining up because I have a rebuilt holley on the shelf perfect for this lol. If it's some kind of weird pattern spread bore intake under there though I'll be sort of SOL although it does run. If it were a pleasant day I'd just see for myself taking the carb off but you guys see all the vacuum connections, and in 20 degree weather thought maybe I'd try here first.

@CorvairGeek I just learned that electric solenoid setup existed on carbs yesterday, kinda novel thing eh.
That would be interesting, I know the wires connecting to it have been hacked with butt connectors.
If you Holley it P.M. me I'm interested in your old stuff.
 

Gene King

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Sorry guys I'm a dumby, I shuffled around the hoses and compared the runner shape to photos online, it's a qjet intake. I tried threading in bolts that looked like a front one but I didn't try hard enough I guess.
Or maybe someone broke off bolts in there, be strange to leave it unbolted for no reason.
 

Curt

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Take lots of pictures and pull the carb off so you can see what’s going on with the manifold.That’s the only way you’ll be able to fix this problem.You gotta have all the bolts in it for mounting.
 

Bextreme04

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are you trying to put them in the top of the carb? The rear mounting bolts are way down on the lower plate in the back and also hold on the throttle cable mounting bracket(the piece that the other end of the return spring and the throttle cable housing attach to. I can see the top of the bracket in your photo, so it seems like the bracket is there and presumably held on by something. Take a pic from the top of the carb as others have mentioned. A single pic from the front of the motor while asking about the rear bolts is kind of a dick move. :Big Laugh:
 

Ricko1966

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are you trying to put them in the top of the carb? The rear mounting bolts are way down on the lower plate in the back and also hold on the throttle cable mounting bracket(the piece that the other end of the return spring and the throttle cable housing attach to. I can see the top of the bracket in your photo, so it seems like the bracket is there and presumably held on by something. Take a pic from the top of the carb as others have mentioned. A single pic from the front of the motor while asking about the rear bolts is kind of a dick move. :Big Laugh:

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Ricko1966

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Is that mixture control solenoid the wrong color for the truck, i.e. a car version vs. the rich/lean only version for a truck? I could be wrong being this is an '86.

Truck version was dual capacity accerator pump, and no throttle position sensor.
 

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