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Holley 2280 carburetor adjustment

My van (82 dodge B250 318) has been running rich and back firing. When I idle no gas drips in the carbs however when I rev the engine gas starts to dump on the drivers side carb. What do I adjust?

Rebuild the carb.

Tester

I don t know how old your carbs are but the ethanol in todays gas eats old carbs after awhile. you may need a rebuild kit. when I finally rebuilt my 75 fords carb, I could not believe the truck still ran, the innards were gone

it was just rebuild last spring

lol. no idea then. hang out awhile, one of these old curmudgeons will know.

At an idle, you should not see any gas dripping from anything. Any fuel/air mix needed at idle is going through the idle circuits, past the mixture needles, and being discharged below the throttle plate.

Carburetors are like engines; there’s rebuilt and rebuilt properly.

that is true. if my son, who is an engine savant, hadn t helped me I would have messed it all up. half of the parts were completely gone and there were little ports and channels to be cleaned that I would not have noticed

As wesw alluded too, are you running gasoline that contains ethanol?

Tester

…and don t use a “new old stock” rebuild kit. the new kits can handle ethanol, old ones can t

True!

The rubber components in rebuild kit can tolerate the ethanol in the gasoline.

But the pot metal that the carb is made of can’t.

Tester

"when I rev the engine gas starts to dump on the drivers side carb."
Can you be more definitive?

When you rev the engine, there should be a spray from the accelerator pump into the venturi, but there should be no liquid fuel and definitely none leaking outside the carb. As mentioned, new rebuild kits contain floats and rubbery bits that can tolerate ethanol, but the old pot metal carb bodies sometimes cannot. If you have porosity in the carb body, there’s no hope for the carb, no way to rebuild it.

If you can better clarify what you mean by gas “dumping” when you rev the engine, we might better be able to help.

I had a great deal more luck installing Ford 2bbl carburetors in place of that Holley or the similar Carter on Mopar products and Jeeps.

I did not know that. my carb is cast aluminium

Cast aluminum can’t handle ethanol either.

Tester

maybe that s why it started leaking around my accelerator pump

Here’s a link to an interesting paper on the subject.
http://www.material.chula.ac.th/Journal/v22-1/61-68%20WIROT.pdf

interesting. I wonder what it would have taken for it not to be considered acceptable.

I learned long ago that studies are often manipulated to say whatever some special interest wants them to say. thank you tester, mountainbike, I learned something

What it would have taken is a lobby more powerful than the one that got it approved that got to the legislators earlier.
Sadly, my friend, that is what this whole ethanol thing is really about… votes and campaign contributions. Oh, and junkets!

my grandfather was a mechanic and took very good care of the van. the carburetor looked pretty good when we rebuilt it and I am confident the rebuild was good and yes I am using fuel with ethanol. I just adjusted the idle mixture screws using my vacuum gauge and its running better. Still a little popping in the mufflers. I’ll have to drive it a little more to see if my float needs adjusting.

Few Chrysler products came with Holly carburetors. Almost all the 318 2V engines came with Carter carbs…So is this the stock carb or has someone replaced the original with the Holly?

After a little checking, I see it’s listed (Holly 2280) for 83’-'85 Dodge trucks…