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Old 07-03-2010, 05:13 PM
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carb loading up and need help

i have a sbc , 11.1 cr, super victor intake, 1 7/8 headers, 950 hp holley,, digital 7 ign system,, cam is 263-273 @50,, have a fogger nitrous kit on it.... last year the car ran perfectly idle a/r was 13.8,,,, fullpower was 12.1,, did about 22 mpg on a run.... this year it is really badly loading up with fuel, so badly that you can only run the car in the garage for 3-4 minutes before your eyes are streaming, it now does around 7-8 mpg.. have been thru the carb gompletely, replaced every gasket in it, have put blanking plugs in front and rear power valves to eliminate them from problem.. have changed the rotor, cap,leads and plugs several times and tried another ign box, redid all the engine grounds, checked fuel pressure and lowered it to 4 psi, ignition timing is at 38 degrees and locked out... nothing has made any difference at all... after running the motor for a couple of minutes the intake is soaked with fuel.. have checked the carb for leaking by raising it off the intake and turning the pump on, not leaking in that condition,, when the carb was off i noted that the screws holding the baseplate were slightly loose, changed the gasket and did then up securely.. again no change,, smoke still pouring out of exhaust.. when the motor is shut off there is vapour rising from the carb for quite a while, never noticed it before..also noticed that if i cover the idle air bleeds in front and rear it increases idle speed and noticeably smooths ou running.. it misfires at idle and gets worse as you get around 3000rpm.... dont understand where the fuel could be coming from .. anybody got any ideas what is wrong here

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Last edited by zephyrc; 07-03-2010 at 05:20 PM.
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Old 07-03-2010, 05:18 PM
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Have you checked the fuel solenoid on the Fogger for a slow leak into the manifold?

How about the needle and seat assemblies??

Air bleeds all clear??

Check the valve lash lately??
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Old 07-03-2010, 05:22 PM
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needles and seat are brand new,, cleaned the carb very thoroughly and all air bleeds and passages are good,,is it really possible for the solenoids to leak like this.. thanks for your very quick reply
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Old 07-03-2010, 05:54 PM
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Yes, it is possible. Just something to check, doesn't happen all the time. more likely if the solenoid sees fuel pressure all the time, ie on a shared line with the carb.
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Old 07-04-2010, 09:23 AM
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removed the fogger entirely today,, no difference... is it possible the intake gasket is leaking around the valley, would that cause this problem
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Old 07-04-2010, 05:01 PM
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Yes, that could be another possibility, could be the reason it smoothes out when air bleeds are blocked.
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Old 07-04-2010, 07:50 PM
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Spray some WD40 around the base plate and gasket and see if the idle raises or lowers. If it does, it's sucking air from somewhere and I'd replace the gasket.
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Old 07-05-2010, 03:19 PM
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removed the intake today and it looks to me like the gasket was leaking at the bottom side in the valley.. i have never used any form of sealer around the intake ports,, can i use sealer there
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Old 07-05-2010, 03:25 PM
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Usually a new gasket will seal that area unless the intake or heads are warped in that area. I usually only put silicone on the front and rear gaskets and around the water ports on the heads to seal off water. Check the surface on both the intake and heads closely where you think it's leaking at for cracks also. Sometime a airline crack will show up and cause that also. Silicone won't hurt, just makes it harder to remove later and more of a mess to clean up.
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Old 07-05-2010, 04:52 PM
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What gaskets are you using?? Aluminum intakes need different gaskets than what is used for iron intakes.
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Old 07-06-2010, 02:33 PM
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r am using the gaskets recommended by dart, 1206.. just ordered some, hope to have it back together at weekend.,. will let you know the outcome.. thanks for the help
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