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Discussion Starter #1
Don't see any numbers on this carburetor (still on the engine)
1 bbl...…..looks like a Rochester.
Has a dead spot at first when you hit the throttle from an idle.
Want to put a kit in it. Any way to identify to get the right kit?

Thx, John
 

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Hi auto or manual tranny the kits are universal to a point. What choke system do you have? heat tube off manifold or spring with a rod. My guess it a BV carb. I bought some kits recently so i can put you in the right direction. A lot of cap out there. the main difference is the year of the carb & the body to air horn gasket The ethenol messes them up. Have you checked the rubber hoses for softness for collapsing cutting off the fuel Let me know I may have what you need I bought a couple of kits recently. I didn't ask is it points or hei?
 

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If you are not into keeping it completely original, I would recommend you move to a newer carb setup.

I am running a 4bbl on my inline 250 - and love it.
 

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Discussion Starter #4
Carb

Ive seen 4bbl on a 6cyl. always thought it would be way too much carb?
why didn't they at least put a 2 bbl on them, don't see that?
 

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Discussion Starter #5
carb

Is an automatic
has automatic choke
has the heat tube (flap that closes in the manifold)
performs well but like I said from an idle, you hit the throttle and it falls flat
then takes off. I can take a photo of it if that helps any
 

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Some chevy trucks with the 250 inline 6 had 2bbl carbs.

Here is a video about installing a 2bbl carb.

 

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Sounds like you might just need an accelerator pump. Easy to replace.
 

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carb Id

Hi John, put up a picture and I can tell you. I can almost guaranty it's a round one. The flat ones were used in the older models. They do make a 2 barrel adapter for the stock manifold. Did you look at the accelerator pump shot on the carb now? Is it points or hei? Did you check the timing, gas filter? All theses will effect your acceleration problem. Trying to help you isolate the problem. Neil
 

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194 Carb Issue

Another thing for you to check---is the vacuum advance cone operating as it should ?? That will cause your flat spot issue as well. The accelerator pump dio is also likely.
 

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had the same problem, sounds like accel pump, Rochester model BC , 1 barrel. NAPA rebuilt kit with the blue accel pump cup worked the best for me.
 

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Ive seen 4bbl on a 6cyl. always thought it would be way too much carb?

why didn't they at least put a 2 bbl on them, don't see that?

They DID put a 2 bbl carb on them ----- in 'South America' .

Those cars with "250ci" motors used a factory 2bbl intake & carb ----------- and, that would be very cool here in the USA.

I might say --- find you a later type carb (like a one barrel carb from a Ford 300ci six ………….. I won't tell anyone.

Back when I had VW type sand buggy --- I hated those 'Solex carbs' .
Then, I had a few ...Ford truck 300 / 6 one bbl carbs , and adapted that onto my VW motor ---=-- It Worked Very Good , and ran well .
Just a thought ----- I'm using a New Holley ( # 8007 ) 390 cfm , 4bbl carb on my 250ci motor , man, it runs Great, (using an "OFFY 4bbl Intake & stock GM exhaust manifold) .

As said --- above --- check your dist. vacuum advance can … make sure it IS Working Good.

later, jim
 

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Hi John that is a BV carb & has a round accelerator pump. Did you check the pump shot ? I ask before you take the carb apart for no reason. Do you know how to check it? I asked in an other post. Does it have points or is it HEI? As someone else asked does the vacuum advance work? Did you check the timing? Make sure the choke is staying fully open.
Neil
 

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Discussion Starter #17
carb

Found a hole on bottom of vacuum line by carb
Carb leaking some fuel also from body gasket anyhow so I pulled.
Only writing I see on it and as in this post Im told its a BV with round acc pump
 

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Garden variety Rochester BV, divorced choke, '63-'65 style. If you do pull the top to replace the top to bowl gasket, do get a straight edge and check both surfaces as best you can for warpage. Classic BV problem is a leaky bowl because the bodies easily warp over time, exacerbated by over tightening of the screws. Accelerator pumps often die early, so it's good to keep a few on hand. Also, even a little leakage of air around the throttle shaft to throttle body bore can make them run rough, so double check the play there.

Let us know how it works out.
 

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While the carb on my 68 is different from yours, I had to go through things and finally got things going well and the car running good.
On mine the car had sat a while and while I never documented closely what I did and how it affected what, I can say I had to go through things like the carb with tightening bolts, adjusting the ignition timing, replacing 40+ year old ignition parts, and some other things but today when I pulled it out to do some checks before putting it away for the winter, it started and ran fine.

I think myself as well as others would like to give a simple answer like it's one thing or another but it could very well be a combination of things.

Things I went through:

https://www.stevesnovasite.com/forums/showthread.php?t=609338

https://www.stevesnovasite.com/forums/showthread.php?t=609698&highlight=gasket

Good luck on your repair.

I do know on mine someone had replaced the carb at some point with one from a 69 Camaro but I did find the right one for the car (68 with the proper date code and part number for a manual transmission) and I did buy a rebuild kit to where I now have some more "winter" projects to work on :D .

Jim
 
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