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Old 11-20-2011, 07:20 PM   #1
danpomeroy
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Carb help

I have a '69 C10 with a 350 and it's an automatic. It is stock except for the Accel Points Eliminator kit and the upgraded coil they suggested. It has the quadrajet 4 barrel that I rebuilt, fresh plugs and wires.

Since I did the tuneup it runs terrible. That's why I rebuilt the carb. That didn't help so I put in the points kit. I have rebuilt a few carbs and I feel good about that, in fact I picked up another one from Craigslist and compared inside and out. I am even more confident that it is right. I am also positive that I did the points kit right. It was pretty easy and it wouldn't start if I hadn't done it right.

The timing is right on, no vacuum leaks anywhere.

The fuel/air screws don't do anything when I turn them. I can turn them all the way in and nothing *Also, when I step hard on the gas, it really bogs down and almost dies. If I drive it normal, it will run but just barely.*

Any help would be SO appreciated.*
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Old 11-22-2011, 09:41 PM   #2
ETsC10
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Re: Carb help

My guess would be the carb...stuck secondaries, float level, ???
I'm sure the guys will chime in with more possibilities...

I had this link sent to me a while back and hope it helps.

Good Luck!
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Old 11-22-2011, 10:33 PM   #3
geezer#99
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Re: Carb help

Hook your vacuum advance to a full time source. THen slow down your idle. Primary is too far open not allowing idle mixture adjustments.
What's your timing set at?
Is your accelerator pump working?
What's your secondary air valve tension set at?
Another link for you.
http://www.digitalcorvettes.com/foru...ad.php?t=88376
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Old 11-23-2011, 02:45 AM   #4
Rooster's 67
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Re: Carb help

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Originally Posted by danpomeroy View Post

Since I did the tuneup it runs terrible. That's why I rebuilt the carb. That didn't help so I put in the points kit.
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Seems to me something went awry prior to the carb rebuild and point replacement kit, Check firing order,possibly crossed plug wires, and for fouled plugs, possibly got an electrode dirty on the way into hole?
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Old 11-23-2011, 05:10 PM   #5
DANTIP
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Re: Carb help

I once bought a decent '72 truck with a Q-Jet on a 350 cheap because the PO couldn't get it started following a carb rebuild without starting fluid. The problem was the choke rod was not attached between the heat-spring and the choke linkage. Make sure your choke is working properly!
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Old 11-23-2011, 11:10 PM   #6
Legolas894
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Re: Carb help

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Originally Posted by Rooster's 67 View Post
Seems to me something went awry prior to the carb rebuild and point replacement kit, Check firing order,possibly crossed plug wires, and for fouled plugs, possibly got an electrode dirty on the way into hole?
Ditto from me-You said you had new plugs and wires. I did that-new carb, new points, plugs, wires but had the #1 and #3 cylinder plug wires reversed. I could drive it but it did a lot of backfires and bad vibes!! Felt dumb after too but the guys on this forum were very forgiving!!
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Old 11-23-2011, 11:21 PM   #7
GASoline71
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Re: Carb help

If you turn the idle mixture screws all the way in and the engine doesn't stumble or die... you've got a wicked air leak.

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I would never rebuild a 305.
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I love using vacuum gauges as part of the carb tuning process. I hook the gauge to the inside of my garbage can and leave it there.
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Old 11-24-2011, 04:50 AM   #8
383longhorn
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Re: Carb help

if the engine isent dying when u screw the idle air screws all the way in then its got a vaccume leak. while its running make sure the choke is off and place your hand just above the primarys on the carb if the engine speeds up then u know its a vac leak. and if you cover up the carb primarys all the way with your hand and the motor dosent die then its a really big leak. a common cause for a q jet to leak is over tighting the back two bolts this causes the top section and even the center section of the carb body to warp and bend. spray a fine stream of brake clean along all the gaskets of the carb while its running and even the intake gaskits. if your exhaust starts smoking white then you found your leak. hope this helps you out!
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Old 11-24-2011, 11:24 AM   #9
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Re: Carb help

You have some good pointers so far. What about the float level. Sounds like it may be too low.
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