Computer Control Quadrajet rebuild

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Geoduck

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My new to me 1985 ran poorly but did run. I've removed the heads and started the Quadrajet rebuild. Just pulled to top off to find......

All 13 top plate screws were finger tight.

It appears the pull-off man shaft was not through the choke lever hole inside the main body.

In the pictures look at the float assy. See anything unusual?
 

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Matt69olds

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Q-Jets are junk!! I just rebuilt it and it still doesn’t run right!!! Get a Holley!!

With that standard of mechanical aptitude, it’s no wonder Q-Jets hace the reputation they do.

How does anyone who hopefully knows which end of a screwdriver to hold make a mistake like that???

I’m surprised it would run without flooding. I figured you would have had fuel coming out the vent Old Faithful style.

Hopefully you have a quality rebuilt kit Cliffs Q-Jet is probably the best out there. I don’t know if he offers parts for the CCC style carbs. He can probably offer some tuning parts to improve on what you have. Keep in mind, the CCC carbs have some special tuning procedures.
 
ChuckN

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Geoduck said:
My new to me 1985 ran poorly but did run. I've removed the heads and started the Quadrajet rebuild. Just pulled to top off to find......

All 13 top plate screws were finger tight.

It appears the pull-off man shaft was not through the choke lever hole inside the main body.

In the pictures look at the float assy. See anything unusual?
Click to expand...
I know there’s a guy that specializes in Quadrajets in Mount Vernon- I could find him again if you’re looking for someone.
 
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Ricko1966

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Don't let the CCC scare you.There's work around to get buy without any special tools not quite as easy but, no one time use tools bought. Don't take out the plugs for the rich/lean stops adjust the mixture control solenoid based off of where the rich stop is currently,adjust to get 1/8th inch travel. You'll need to r&r the air horn to make adjustments. Other than that it's basically just regular qjet,don't forget to checkbthe tps for erratic readings while you have it off. Bad tps makes them go full rich.
 
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Geoduck

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Matt, I did in fact order a CCC kit from Cliff's. Should be here this weekend. :)

Just removed the pieces after soaking overnight in 50-50 water pine-sol. Very clean and looks nice.

Thanks for the tips everyone much appreciated! I am NOT an expert.

Chad, if it fails to function correctly I would like that guys contact info. My son is going to Western State in Bellingham so we pass by there often.
 
ChuckN

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Geoduck said:
Matt, I did in fact order a CCC kit from Cliff's. Should be here this weekend. :)

Just removed the pieces after soaking overnight in 50-50 water pine-sol. Very clean and looks nice.

Thanks for the tips everyone much appreciated! I am NOT an expert.

Chad, if it fails to function correctly I would like that guys contact info. My son is going to Western State in Bellingham so we pass by there often.
Click to expand...
I had to do some digging as I happened across them back in June, but apparently it’s Zip Tune, and is a NAPA service center. Phone number is 360-336-2667. I’ve not used them myself, but I had called them in my friend’s stead and they confirmed that the main guy has been working on Q-jets for years.

Sorry for the late reply, I just saw this your post @Geoduck .
 
Geoduck

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Much appreciated Chad. :)
 
Geoduck

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Ricko1966 said:
Don't let the CCC scare you.There's work around to get buy without any special tools not quite as easy but, no one time use tools bought. Don't take out the plugs for the rich/lean stops adjust the mixture control solenoid based off of where the rich stop is currently,adjust to get 1/8th inch travel. You'll need to r&r the air horn to make adjustments. Other than that it's basically just regular qjet,don't forget to checkbthe tps for erratic readings while you have it off. Bad tps makes them go full rich.
Click to expand...
Rick,
I appreciated your detailed suggestions.
After some research I was very confused. Come to find out the carburetor on my truck is not stock. It's the correct year but for a manual not automatic. Also its not an E4MD type.
I'll finish the carburetor rebuild tomorrow but won't have the engine back together for a few more weeks. Will return here with results.
 
Doppleganger

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Mine is also an 85 and had that same QJ. I sent it to Mountain Man in AR and they did a stellar job rebuilding it. Problem was, the idiot PO cut all the wires under the hood so I couldn't use it anyways (without calling NASA) - so I went FI and the 'new' QJ remains in the box.

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Ricko1966

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@doppelganger @Geoduck doppelganger picture is of a dual capacity accelerator pump qjet, not a computer controlled qjet. Almost identical to a standard quadrajet and will run fine with no electric inputs except for the choke. @Geoduck Is this the carbureator you have? Not one with a mixture control solenoid and throttle position sensor. If so that would explain both of our confusion. I looked at the title and gave you instructions for an actual computer controlled quadrajet.If this is the carb you have and rebuilt it like a standard qjet,it's going to work fine. Damnit ,it's that year make and model thing, ccc was California only 86 only to the best of my knowledge I could google it,to double check,that would make some members happy.
 
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Doppleganger

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FWIW, my 85 was from Eugene OR - everything on it was Cali-spec.

Glad to know all the differences.....I think.
 
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Ricko1966

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Doppleganger said:
FWIW, my 85 was from Eugene OR - everything on it was Cali-spec.

Glad to know all the differences.....I think.
Click to expand...
Well it's good news if you or a friend ever need a qjet for anything, the grey plug on top just controls accelerator pump shot disconnected you'll just get a full shot all the time. If you want to hook it up that's not hard either,but old school qjets were full pump shot always..
This is the tell tale of a ccc qjet a plug for the tps
 

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