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Discussion Starter · #1 ·
My 235 six had been acting like the accelerator pump had stopped working. When I stepped on the gas quick, the engine would almost die and then catch up and run fine. It started getting worse, so I decided to pull the carburetor and tear it apart and see if I could figure out what was going on. I had rebuilt it earlier in the year with a rebuild kit I bought off eBay. Well, the accelerator pump shaft had a red in color rubber/neoprene piston on it. The old one had a leather one on it. The rubber must have not been made of fuel proof material as it swelled up and was loose on the accelerator rod and half again larger then when I installed it! I could hardly move it up and down the accelerator bore wall because of it being too large. Since the piston is actuated by spring pressure, it was too tight in the bore and would not move up and down as it should and the spring compressed instead of the piston moving and squirting fuel in the throat of the carburetor causing my problem. I’m going to take a wild guess and say this kit I installed was made in good old CHINA.
Anyway, this post is to let you folks that rebuild your own like I do, to check your kit before installing it for this problem. If the piston is red in color and not black or leather, you may have a problem down the road with the accelerator pump. A black rubber piston may not be any better than the red one if made in China, but my other kits with the black rubber gave no problem.
Just thought you all should know!
 

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Discussion Starter · #4 ·
angs1957 Please let me know if you do come up with a modern direct replacement.
Thanks
 

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don't' know if there is a 1bl replacement, but looked into a 2bl upgrade.

the problem that I ran into was hood clearance. I called the stovebolt guy all ready to buy this adapter and get the carb from him as well

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When he asked for my hood clearance it was to low. 55 and 56 seemed fine, but I was kinda SOL with a 57

he said there may be a Pinto one that may work, but I would have to call him back a few months later when he got them in.

the best solution is to go with a 4bl intake,


but that means you need to get exhaust headers as well.


so for now...I'm still stuck with the old 1bl :-(
 

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Discussion Starter · #6 ·
jerrspud, I'm in the same boat and my 57 seems to match yours closely. I don't mind a few non original items, but I want it to look as close to stock as it can by the casual on-looker. I don't want or need to bolt on a lot of new manifolds and such for a big power boost, but the stock carb seems to work kind of crappy, but it does work. Something of newer design that will help it idle smoother and accelerate without stumbling would be great. Maybe someone will start selling something like that. There are a lot of old 235's and similar engines out there that folks still have running and they would love to buy an upgrade direct fit carb at a decent price!
 

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I don't know if there is a modern single bl out there. Won't any single bl have terrible low end?

here is some info on the rochester BC
http://newagemetal.com/pages/ServiceProcedures/B/57-61ModelBDesignChanges/index.htm

info on rebuilding, and other single carbs that might work
http://www.classictrucks.com/tech/0802ct_rochester_carburetor_rebuild/index.html


I think the best 235 info comes from the stovebolt guys.

some possibilities
http://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=656886#Post656886


here is some better info
http://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=79567
I had two Carter YFs, which are better than the Roch Bs but the Carter W-1s are really ideal for a street 235.

the carter W1 is old last made in 50
The last W-1 was 1950

also...while I was digging around the site I read that someone makes the old leather pumps by hand

in the end you can call Tom Langdon and ask what he thinks. I don't think he sells any singles, but you can ask. I'm saving up for the 4bl :)


he also has the adapter for modern tranny if you have an old powerglide
 

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No matter which carb you choose you may still have the same problem with parts deteriorating. The problem is not the Chinese it is the Americans...the ones running the E.P.A. Our cars were designed to run on gasoline, not ethanol. I have put in more carb kits in the last 5 years than I did in the 45 years before that.

Cars with carburetors are in the minority and declining in numbers every year. The parts companies are not interested in spending a lot of money on R&D to find something that will hold up to ethanol.
 

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Discussion Starter · #9 ·
Tabasco, I think you are right. I haven't thought about the "new" gas we are using now. That may just be the trouble. I might have been too harsh on "China". I wonder if they make a fuel injected one barrel carb replacement. I know they do for a V8 setup.
 

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235 carb?

good info on the carb. kits, need to do the same on my belair but where and what carb. kik can be used?
will the gas additavies help slow down the cause?
 

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A Clifford 4bbl intake and a 390 Holley 4bbl, although I have heard that the 390 carb needs to be tuned for the 235 install and will not run correctly out of the box. I have seen others run the larger 4bbls, and a very few others that have messed with the 350 cfm 2300 2bbl (which is not an actual 350 cfm as compared to a 4bbl but is closer to 280 cfm in comparison. The 4bbl and 2bbls are rated using different levels of vacuum which is why the disparity in comparisons.) I have 0 experience with either 2 or 4 bbl carbs on a clifford manifold so not much help other than the above (I like the look of multiple carbs).
 

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And you fellows might be a little harsh on EPA also -- it's not the gas, it's the gaskets. If you're using a 20 or 30 year old carb kit, it won't hold up to modern gas. You can buy new carb kits that can handle modern gas for most popular old carbs, but I haven't found a new kit for a Rochester one barrel on the market anywhere. Please correct me if I am wrong (and I know you will).

When I rebuilt my one barrel Rochester in my 56 last year, I ended up using the old leather accelerator pump because I knew the new rubber/neoprene supplied one was crap right out of the box. So far, no leaks and all is working well together.

What we need to do is find someone here in the US carb gasket business who will reproduce carb kits with modern materials. I'm sure they have the dies or access to them already.

Gregg.
 
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