The Stovebolt Site Forums The Shop Area Engine Shop Rochester "B" carburetor question?

Been reading various posts concerning the Rochester "B" carburetor, the Carter "YF" carburetor and the Zenith carburetor. Why are the Rochester "B" carburetors looked down on versus the Carter or Zenith carburetors. I have a Rochester "B" on my 1949 Chevrolet 1/2 ton with the 216 cu.in. engine and have not had a problem with the Rochester, even after rebuilding it.

Tim

It's just the "law of averages", nothing more.

If I say, "______ is superior to _______" it is a purely subjective statement. All the Rochester B (and BC) carburetors I have used leaked a little, but they worked. All (just 2) Carter YF carburetors I've used didn't leak, and they also worked. No experience with Zenith except on a boat that had a busted hull, so I don't know where they stand (on leaking). (Lol, pun not intended)

You're sorta answering your own question...
Since you have not had a problem.

Brad

Carb King and Hot Rod Lincoln will have a field day with that question! hehehe

I have the Rochester on my 261 which a friend donated to me. I just started the engine and ran it a good bit. the carb is fine.

From reading MANY post/opinions here on the bolt over the years one thing I have learned. GM generally built and specified a carb based on the need of the engine or engine size. Since one particular carb will work on many engines it may not be that the one folks have on their engine, and complain about, is not the one GM intended to be on the engine. Thus the carb gets a bad rap. I know some have "warping" issue's and some have "leaking" issue's and some "jetting issue's". However, if one turns to the pros we learn that most carbs can be fixed to run very well. I've had good, and bad, issue's with several different ones!

We generally have to use what we have so do it once, do it right.

The Roch B on my 49 216 works flawlessly (knock on wood). I don't believe it was the original as it was much cleaner than the rest of the engine. But I took it apart, cleaned it up and installed a new kit in it about 13K miles ago and so far no leaks, slips nor drips. I'll guess it was the 1st time it was rebuilt.

That said I tried 2 different/slightly larger Roch B's on a 235 I rebuilt and couldn't get neither to work right. And they both leaked from the housings joint.
A couple Carter/Webber 32's straightened the 235 out.

Thanks guys for your input on the carburetors. From my readings it appears the Carter carburetors were the OEM choice at the time of production in 1949. Is there a true advantage to the Carter carburetor? It appears that the Carter carburetor issued for 1949 was a W-1 730S. Where would I find this carburetor? I have checked E-Pay and various other carburetor sites on the internet, but have not been able to find the a W-1 with the 730S designation.

Tim

When Chevrolet made the decision to stop buying Carter carbs as original equipment in the late 1940's and substitute Rochester (owned by GM), the CEO of Carter vowed to sell a million replacement carburetors for Chevy. It took him several years to do it, but when the millionth Rochester replacement carb came off the assembly line, he had it gold plated and presented it to the CEO of General Motors! Dad's shop was an authorized Carter distributor, so we had lots of discarded Rochesters stored in 55 gallon drums. Rebuilders used to buy them for about $2.00 apiece. If I had a few hundred of them now, I'd be an Ebay tycoon!
Jerry

Tim, I'm going to a yard today that may have one of the Carters

If I remember correctly, CarbKing once said about the Carter W-1, an advantage it has is the accelerator pump. The pump on the Carter is made of leather, so it is not prone to degrade with modern alcohol blended fuels that are almost everywhere nowadays.

I had planned to avoid this thread, however there are some misconceptions that need addressing:

Tim: the Carter WAS the O.E. carburetor of choice in 1949, however it was a 684s (W-1), not the 730s (WE).

The 730s type WE was an AFTERMARKET carburetor sold for use on Chevrolet, NOT O.E. It basically is a 715s (Studebaker) carb with slightly different calibration and a Chevrolet arm. This is why you have not found a 730s W-1, as it doesn't exist.

Yes, ALL Carter W-1 carbs did come with the leather accelerator pump, but in fairness to the Rochester type B, so did the early Rochester type B. It wasn't until later (early 1960's) that Rochester cheapened the B with the neopreme pump. The really good carb kits for the Rochester B STILL have the leather pump.

Jerry - you mentioned that the rebuilders paid about $2. each for the B's; I HAVE BEEN TRYING TO GIVE THEM AWAY!!!

http://www.thecarburetorshop.com/Free_carbs.htm

So far, in over 5 years, nobody has taken me up on a free Rochester B! I have given away a few of the Zenith and Holleys also listed in the link.

Jon.

Jon,

Why would you not want to jump in here!!?? With a screen name like "carbking" ... and that's what you do ... this is perfect.

Glad you chimed in.

Peg

And since I broke my resolve to post in the thread, maybe a little addition information might be interesting.

Sometimes one may glean additional information about a product by looking at other products by the same company. So, a bit of a history lesson.

Rochester built their first carburetor in 1949. It was a series A and a two barrel. As other carburetor manufacturers (Holley, and Stromberg) had a "convention" of using a double series letter to denote a two-barrel. The 1949 Rochester was designated type AA (Oldsmobile). But Oldsmobile also used Carter. The AA was contined by Oldsmobile through 1950, and at the end of 1950 the series AA was thankfully discontinued.

The first series B carb was sold on the 1950 model Chevrolets. But did you know there was a two-barrel model B? Using the above convention, it was designated BB and used one year and one year only by Oldsmobile and Cadillac (1951). Wonder why it was discontinued, and replaced by the series G??? Oh, and both Olds and Caddy also used Carters in 1951.

To date, I have yet to sell my first type BB carburetor! And in 40 plus year of selling kits, have sold about 3 kits for the BB. Wonder why? Yet we sell lots of kits for the 1951 Olds and Caddy Carters.

The series G was produced in both a two-barrel and a 4-barrel. Stromberg had a 4-barrel beginning in 1952 which was called a 4-A (I guess AAAA would have been awkward). Likewise the two-barrel G was a 2G, and the 4-barrel G was the 4G. These continued with the single B (and later the H on the Corvair) until the series M. Since the M had a vacuum break, it was named an MV (1 barrel) a.k.a. monojet, and the 4-barrel was named a 4MV a.k.a. quadrajet.

But note there was NEVER a 4B and the BB two-barrel lasted only a single year.

Jon.

I just wish the 261 versions were more available. So far I have two 261s that need one. Someone came by the other day and showed me a 292 version that had a larger throat, but not as large as the 261. Thanks for the input Jon!

Great info; and, as a clarification if there is any confusion... (and to validate that I have read AND comprehended all carbking/HRL/others carburetor advice here on Stovebolt):

I have a Carter YF 2100s installed on my 55.2 truck's 235, and I have an identical spare Carter YF 2100s ready to install should it be needed.

I will not be purchasing a Rochester B(or BC) rebuild kit for the ones I have that need rebuilding.

Brad

I installed a zenith carb off a 1957 gmc 270 on my 261 chevy... runs great and have decent mileage. I still have the original larger 261 Rochester but it didn't perform as well ... even after a rebuild ... its the larger Rochester made for the 261..

A bigger pile of bovine effluent doesn't necessarily mean it's better!
Jerry

Today's internet traffic will reflect a google/Wikipedia search engine spike for both "bovine" and "effluent".

Brad

Jon,

Thank you for responding to my inquiry! I was hoping you would chime in. The information given was very informative and now has led me down the correct path.

I have been trying to find the brass I.D. tag for my Rochester "B", but to date no success. I see that you have posted on your website that due to "legal ramifications" the carb tags are no longer sold. Is that why I am not able to find a replacement tag? Is it possible to obtain one?

Again, thank you for you knowledge and information. I will continue my search for a 684S W-1 instead of the non-existent 730S.

Tim

Tim - give me a call. 573-392-7378 (9-4 Mon-Tues central time).

The 684s is correct for a 1949; but since it is a one year, one make, it is expensive, and parts are ridiculous.

If you don't have to have the fast idle, the 1948 carburetor 574s is just as good, and less expensive.

Jon.

Jon,

I will give you a call Monday. Look forward to the discussion.
Thank you again!

Tim

I came across 2 Carter W-1's today, neither has a tag. I can't tell if they are 684s or 730s or another designation. How would I decipher what they are?

I'm operating from poor memory here.

Don't GMCs mount 90 degrees offset to what a Chevy would? Like the GMC throttle body would run parallel to the engine and the Chevy perpendicular?

I ask because I'm always on the lookout for a zenith. But curious how you overcome that issue.