weber carb needs choke to run

[2sixTZombii]

I have been fighting the same problem for awhile now. One carb needs choke to run, the othef does not. So I rebuilt, same problem, so I swapped carb from one side to the other, follows the carb, swapped tops from one carb to the other, stays with carb body, doesn't follow the top. Pulled rebuilt again much much more throughly, eun way better, still needs choke on thay carb. I did so much adjusting that my head hurts, so thats not it. I can actually see fuel coming out on this one so if anything its running rich, but needs choke. The other carb hasn't been rebuilt so I was maybe gonna try that, but can't see how it could be the problem. I am on a low budget and afford new carbs, used yes, but not new, I am considering buying the four barrel manifold on ebay but really want to keep duels. I am willing to just buy another weber used and rejett/rebuild but I can't tell whats wrong with this one, nothing as far I can tell, but I've narrowed it down to almost having to be something in the bottom of this carb. Anybody have any clue, these worked fine back in the 90's before it sat so WTH???

[djwarner]

I'm certainly no expert on carbs, but it seems to me that if it runs with the main throat blocked, the air must be coming from somewhere else.

You don't say whether you are applying full choke or partial choke.

As disparaged as the DGV's are, I would think you can buy a used replacement carb cheaper than a four barrel manifold.

[Kurbycar32]

I have DVG's and they get more hate then they deserve. While SU's are higher performing carbs DVG's will operate your vehicle reliably and theres no reason they shouldn't work.

All that aside dj eluded to your real problem: vacuum leak. Your problem sounds like a massive leak so check the usual places like ports and lines but also consider your intake/exhaust manifold gasket. Theres a thin paper gasket between the manifold and the carb body, you might be missing one of those too.

[2sixTZombii]

I thought vacuum leak too, but it can't be unless its in the actual carb body, which I'm wonder if its actually cracked. The problem followed the carb from one end of the motor to the other and it has new base gaskets on both carbs. If it followed that carb from one end of the motor to the other, then it can't be a leak anywhere below the carb base. A couple other strange things to note, it makes a Strange whooshing noise. And when I spray gas or carb cleaner down where the emulsion tubes are visible its bogs down and almost dies, but on the good carb it picks up when I do the same thing.

[Kurbycar32]

I purchased a set of brand new DVG's a few years ago and while they definitely needed adjusting they ran the motor with out of the box settings. Short of physical damage i cant think of any reason new carbs are required here and you have one of the most popular carbs in your hands so parts are super easy to come by. My recommendation is to put both carbs on your bench or kitchen table (if your single) and go through the rebuild process on each, setting each carb to the factory setting. You mentioned you already rebuilt one so for that one just disassemble and return to factory specs, take note of the seals and reassemble. Do one carb at a time in case you need to use the other as reference.

[beermanpete]

What do the plugs look like?

From what you have said, I suspect the idle circuit is blocked or damaged. When you rebuilt the carb did you verify ALL passages are open and will flow fuel and/or air as required? What does the idle mixture screw look like? If the tip does not come to a point it could be broken off and stuck in the passage causing a blockage.

[2sixTZombii]

What do the plugs look like?

From what you have said, I suspect the idle circuit is blocked or damaged. When you rebuilt the carb did you verify ALL passages are open and will flow fuel and/or air as required? What does the idle mixture screw look like? If the tip does not come to a point it could be broken off and stuck in the passage causing a blockage.

Rebuilt(not working) carb side has three sooty plugs, good side has three mediocre dark brown plugs. Replaced them all 4 times. The first time I rebuilt it I kind of just cleaned it and slapped in some new parts, second took everything apart and thrpughly cleaned and checked every passage or jet. When it runs you can here what almost sounds like an vacum leak inside the carb, kinda makes a slurping sound. I checked the base again today and found nothing suspicious. I saw a couple rebuildable DGVs on ebay for around 50-60 I am thinking of getting one and rejetting it to match my good carb. But I really can't figure how mine could just be shot, this has a 280 hood sans vents so it sat for 12 years with carb open to the elements(albeit with an air cleaner) but I can't see how that could of caused permanent damage. I thought about rebuilding the other carb, just to see, but I just see how any way that could be the issue.

[2sixTZombii]

I was wondering if the air corector jets could be my issue, not sure WTH they even do, but they have air in the title, they were throughly cleaned, and the passages were flowing fine.

[beermanpete]

Sooty plugs means it is too rich. Look at the float. Perhaps the float is bad and has taken on fuel. This will cause the float to be less buoyant and sit low in the fuel, causing a high fuel level.

[2sixTZombii]

Float level is set right and proven good, honestly the running rich is mostly a matter of adjustment, I've been able to adjust it out before. It needs choke to run though and I can't see how its running rich could cause that.

[beermanpete]

How did you "prove" the float level?

[2sixTZombii]

How did you "prove" the float level?

I think you misunderstood me, I proved the float itself was good, not the level. I did so but using a screw driver to hold down in a large glass of gas for awhile. then unhooked the screw driver and it shot back to the top. I suppose I know the level is adjusted according what I read on I think it was the peirce manifolds site.