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Old 11-18-2006, 02:12 PM   #1
Blue85
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Q-jet Carb Trouble

my carb seems to automatically flood as soon as i turn off the truck, it will start fine cold, but after its warm it will not start without flooding. It also leaks fuel out of the throttle rod bushings at the base when I shut it off.
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Old 11-18-2006, 02:13 PM   #2
neonlarry
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Re: Q-jet Carb Trouble

Leaky fuel bowl plugs and worn throttle shaft. Time for a complete rebuild.
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Old 11-18-2006, 09:09 PM   #3
PICKMUP
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Re: Q-jet Carb Trouble

If it starts good cold, there is fuel in bowl so plugs are probably holding OK. May be needle & seat not holding. Carb kit may cure it.
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Old 11-18-2006, 09:28 PM   #4
Livrat
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Re: Q-jet Carb Trouble

If it is not running rich all the time i may be possible that someone over tightened the front two bolts and warped the top of the carb.. A common problem with Q-jets, When that happens it will leak fuel into the venturis when you shut it off flooding the engine..
Here is a link to a bit of info..
http://www.quadrajetcarburetors.com/
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Old 11-19-2006, 06:22 AM   #5
JimKshortstep4x4
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Re: Q-jet Carb Trouble

If the float level and needle valve is ok, I would suggest replacing the float. The Q-jet floats can absorb gasoline over time making them not seal the needle valve and seat completely. When the engine is running it will burn the excess fuel but when the engine is shut off pressure from the pump will push fuel into the carb causing it to flood.

Jim
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Old 11-19-2006, 09:00 PM   #6
Blue85
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Re: Q-jet Carb Trouble

forgot to mention this carb was rebuilt w/ a new float a couple of months ago, now the guy that rebuilt it has left town so i may be out of luck
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14 Dodge 3500 Mega Cab
08 Dodge 3500 Mega Cab
87 Chev 3+3 4x4
80 GMC K10 High Sierra bone stock
70 Chevelle 350SS long term project
68 GMC 3ton Grain Truck/Garbage wagon
50 Pontiac 2 Door Coupe Project
"I've got a shotgun rifle and a 4 wheel drive and a country boy can survive" Hank Jr.
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