Bad idle problem

[hatred]

Truck is a 70 Chevy with a built 350 in it. Replaced intake, put in brand new distributor, carb is an Edelbrock 1406/1407 (hafta double check) manual choke. If it sits without being started for 4-5 days, you have to pour a little gas into the carb, once it starts it will star perfect, and idle fine. Drop it into reverse/drive and it acts like you unplugged 7 spark plug wires. Plugs are new, wires came on it. Once in gear it has no balls at all. New inline fuel filter, no filter in side of carb. You can also smell it burning alot of gas when its just sitting there idling. I cant find any vacuum leaks at all, but havent check the line to the transmission valve yet...

Any ideas or pointer?

Thanks,

Tony

[Wrenchbender Ret]

Sounds like the carb is running rich & getting soot on the plugs. Does the choke go off all way when you push in the cable? Do you push the cable in after it starts? Pull out a plug or 2 & see if they are carboned up. If the choke isv OK you may have a carb. problem

[hatred]

I've tried adjusting the air/fuel mixture but even turning them both all the way in changes nothing. Doesn't even make it die. I'm thinking the carb is junk but wanted other ideas.
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[Wrenchbender Ret]

I wouldn't call it junk but it probably needs a kit & freshening up.

[cdowns]

what type fuel pump?

[hatred]

Fuel pump looks to be a stocker, and not very old. Havent checked the in tank filter yet. Tank is barely full now so this would be the best time probably.
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[oklalawnboy]

I'm sure you checked the timing.

[hatred]

Yeah timing is good also. Starts on the first hit.
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[dmw319]

Sounds like the carb to me also. Rebuild it or buy a new one!

[Todd Hepler]

I have owned a few vehicles with these carbs.

They are very sensitive to trash in the fuel bowl and high fuel pressure.

Both conditions cause the symptoms you are describing.

When you are experiencing the rough idle, look into the venturis and see if there is fuel dripping - if there is the first thing I would suspect would be for a stuck float valve or 2.

The nice thing is that this is a really easy problem to fix: pull the carb off and clean it out with a bit of carb cleaner and you're good to go. 30 minutes tops, and usually no new gaskets required.

Good luck,

Todd

[GASoline71]

Originally Posted by hatred

I've tried adjusting the air/fuel mixture but even turning them both all the way in changes nothing. Doesn't even make it die. I'm thinking the carb is junk but wanted other ideas.
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If you adjust the air mixture screws all the way in and it still runs... you have a vacuum leak. The intake gasket could have slipped during installation, and not sealed properly to the heads. Been there, done that...

Originally Posted by hatred

Fuel pump looks to be a stocker, and not very old. Havent checked the in tank filter yet. Tank is barely full now so this would be the best time probably.
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There have been some cats on here that have had to run a fuel pressure regulator for the Edelbrock carbs. They only like about 5psi. Anything more than that it will run like crud.

Originally Posted by dmw319

Sounds like the carb to me also. Rebuild it or buy a new one!

A Holley!

Gary

[ole dollor]

hatred: did you just replace the intake, did it run ok before you replaced the intake...or has it always run like this.....more info if ya can...

[hatred]

Originally Posted by ole dollor

hatred: did you just replace the intake, did it run ok before you replaced the intake...or has it always run like this.....more info if ya can...

It ran the same. I've sprayed carb cleaner around the intake/carb and havent noticed a vacuum leak. I was very careful of the gaskets when I dropped the wiend intake on it. Maybe I'll try a regulator also and see if that helps. It's dumping so much fuel it will run you out if the garage even with all four garage doors open.
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[hatred]

Bump...


Might try to find a local carb to borrow this weekend. See how that goes...