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Topic Review (Newest First)
10-07-2009 04:11 PM
hatrecide i checked the metering blocks and they dont seem to be warped. i did fail to mention that i have tryed 2 different carbs one 4150 custom and a new out of box 4150 street and both had the same problems. i have disconnected the brake booster hose capping of the port and till has the problem.
10-07-2009 10:57 AM
hatrecide yes i have a breather cap on the valve cover
10-07-2009 06:48 AM
sqzbox So, you have "open" breater cap's on the valve covers? or a breather hose going to the air cleaner?
10-06-2009 11:20 PM
hatrecide this car doesnt have a pcv valve (positive crankcase vent) if thts what you mean
10-06-2009 10:44 PM
sqzbox And the PCV valve?
10-06-2009 10:15 PM
hatrecide ok i checked today and i am for sure using the correct one
10-06-2009 08:59 AM
sqzbox Check your using the right gasket between the metering block and the body.
one has an open area above the power valve that uses a small O ring gasket.
that that makes up the difference in the recess.
One has no open area with a small hole that seals to the body for a flush mount. This is the accelerator pump transfer hole.

Use the wrong one and your going to have problems/flooding at idle.
This is one problem with universal kit's to rebuild several different models, it's easy to get the wrong parts or gaskets put in. This is why they say in the inst. to compare closely with the part/gasket your removing. Failure to get the right gasket in there will suck fuel out of the accelerator pump reservoir into the area behind the power valve. That will eat up the diaphragm on the power valve over time. Now, with that vacuum area full of fuel, the vacuum port that feeds the signal to the power valve will be sucking fuel also causing an over rich idle condition.
10-06-2009 05:48 AM
cobalt327
Quote:
Originally Posted by hatrecide
everytime i rebuild the carb new gaskets/power valve the problem goes away but slowly returns
Check the metering block/body for warpage.
10-05-2009 09:47 PM
hatrecide could it be that the power valve is to small and possibly being sucked open the whole time and flooding the engine i dont have a vacuum gauge but i was thinking big cam less vacuum so i got a 3.5 in there
10-04-2009 04:16 PM
hatrecide ok i tried a few options i got a reo pump brown cam position 2 and it seems like the stumbles gone, the car idles 2000 in neutral/park and when i switch to a gear it doesnt stay running almost like its loading up. it seems like everytime i rebuild the carb new gaskets/power valve the problem goes away but slowly returns until it doesnt run in any gear park or neutral.
10-02-2009 08:31 PM
cobalt327
Quote:
Originally Posted by hatrecide
the intake is a edelbrock supervictor
That single plane intake will require more fuel than 70's, most likely. What are the plugs saying?
10-02-2009 05:03 PM
dawg
Quote:
Originally Posted by hatrecide
ill try some of these idea tomorrow because of weather conditions, but the brake booster is brand new like 1 month old, the intake is a edelbrock supervictor 9.2 in between the carb and the manifold is a nitrous plate. it seems like it idels fine then i put it in 1st it die i restart it then it is fine after that
I went through 2 NEW boosters before i got one that didnt leak.
In this day and age NEW doesnt mean its good!
10-02-2009 02:26 PM
sqzbox Sounds like a mopar!
10-02-2009 10:55 AM
hatrecide ill try some of these idea tomorrow because of weather conditions, but the brake booster is brand new like 1 month old, the intake is a edelbrock supervictor 9.2 in between the carb and the manifold is a nitrous plate. it seems like it idels fine then i put it in 1st it die i restart it then it is fine after that
10-02-2009 06:54 AM
sqzbox What kind of intake do you have? Any spacer under the carb? Could be a velocity thing in the plenum. There's also a problem called reversion. With a high lift, long duration cam, when the cylinders are getting more than enough air, the pressure builds up to the plenum and will try to spit excess air and fuel back through the carb resulting in a md-range stumble. Check the under side of the air cleaner lid after a hard run for evidence of fuel on it.
I'm old enough that I can't remember how to correct it guess I'll have to read up on it again if I can find the info.
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