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numbering systems Carter used two
different numbering systems; the one used for Chrysler Corporation, and the
one for all other customers. If the Chrysler
system is coded, I have not found anyone who knew the code. It would appear
that the number which is the first character in the string represents the
engine number of cylinders. The system used
for all other customers was a number, followed by the letter "S" as
in (S)am. The numbers were assigned sequentially, at least after about the
year 1925. SOME carburetors will have another letter which follows the
"S", most do not. The most common second letter is a "A",
as in (A)pple. No, the "A" does NOT mean automatic transmission. In
Carterspeak, there are "parts", and there are
"assemblies" which are composed of parts. The "S"
following the carburetor number means assembly. To illustrate, an idle
mixture screw is a single part, thus would NOT have the letter S appended to
the number. A typical idle mixture screw might carry the number 30A-35. A
fuel valve is an assembly; as it is composed of a needle, a needle seat, and
the needle seat gasket. As it is an assembly, it would have the letter S
appended to the sequential number, such as 25-48s. Now the second
letter. The second letter is an engineering change status. The FIRST time a
minor engineering change was made in the carburetor (maybe changing an idle
jet from 0.023 to 0.0235), the letter "A" would be appended to the
letter S. A typical example would be the 871s was changed to the 871sa. The
second change would see the second letter changed from an "A" to a
"B" or 871sb. The third change the letter would become a
"C". The 871s did in fact have three minor changes, so the final
version was a 871sc. Casting
numbers It is
IMPOSSIBLE to identify these carburetors solely by the casting numbers, as
the castings were machined differently for different applications. The
casting numbers are listed to aid in identifying "marriage"
carburetors. Fuel
pressure For those who
plan on installing a BB-1 on other than the original application, one should
be aware these carburetors were used on vehicles with "gravity
feed" fuel systems as well as vehicles with pressure fuel pumps. Carter
released four different fuel valves with orifice sizes from 0.085 inch to
0.118 inch depending on the pressure of the fuel delivery system. Using the
large valve with a pressure pump can cause flooding to the extent of fuel
always leaking from the carburetor. Using one of the smaller valves on a
gravity feed system can result in fuel starvation. Identification Index 245 | 257 | 262 | 289 | 447 | 489 | 517 | 586 | 638 | 640 | 641 | 699 | 745 | 871 | 2035 | 2075 | 2212 | 3377 | 4403 4A1 | 4A2 | 4A3 | 6A | 6A1 | 6B1 | 6B2 | 6C1 | 6C2 | 6D1 | 6D1R | 6E1 | 6F1 | 6J2 | 6J3 | 6K1 | 6K2 | 6K3 | 6M1 | 6N1 | 6N2 | BB1 Applications Index Chevrolet | Chrysler | Chrysler Marine | DeSoto | Dodge | Federal | Gray | Lycoming | Owens | Plymouth | Universal Manufacturer Section
(Chevrolet 839041) - The 447s carburetor was used as original
equipment on Chevrolet 216 CID 6 cylinder engines in 1939 and 1940. This
unit has an S.A.E. size 2 mounting flange, and a 1 inch internal
venturi. The throttle bore is 1 7/16 inch. There are no identification numbers on the 447s castings.
(Chevrolet 839515) - The 489s carburetor was used as original
equipment on Chevrolet 216 CID 6 cylinder engines in 1941. This unit is very
similar to the 447s which it replaces. The S.A.E. size 2 mounting flange
is retained, as is the 1 inch internal venturi, and the 1 7/16 inch throttle
bore. The calibrations were tweaked slightly from the 447s. Other changes
include a new choker valve and shaft, the elimination of the "fast idle"
linkage, changing the pump dust cover from a "floating" weight to a
sandwich of two weights and a felt seal held by a retainer, and a different
method of internally sealing the main venturi. There are no identification numbers on the 489s castings.
The 517s was introduced as original equipment on the 216 CID
Chevrolet engine in 1941, and was continued in use through 1948. While the
517s retained the S.A.E. size 2 mounting flange of the 489s, the internal
size was increased as the main venturi is now 1 1/16 inch, and the throttle
bore is now 1 1/2 inch. The calibrations were tweaked to compensate for the
greater air flow
The 699s was used as original equipment on the 216 CID Chevrolet
engine in 1949, superseding the 517s. Physically, the 699s retains the same
S.A.E. size 2 mounting flange, the 1 1/16 main venturi, and the 1 1/2 inch
throttle bore of the 517s. Idle jets were slightly increased in size
(richer), while the main metering jet was slightly decreased in
size (leaner) and the power jet was significantly decreased in size (leaner). The 745s was used as original equipment on the larger 235 CID Chevrolet
engine in 1950. S.A.E. mounting flange was changed from the size 2 of the
699s to a size 3. Likewise the throttle bore was increased to 1 9/16 inch and
the main venturi was increased to 1 3/16. As the carburetor now flowed more
air, the jetting was increased to match the airflow. 871s, 871sa, 871sb, 871sc - 1950~1956 (235 CID engine) - The 871s unit was introduced in 1951 on the 235 CID Chevrolet
engine, replacing the 745s. The 871s, and its upgrades (871sa, 871sb, and
871sc) were used through the 1957 model year on the Chevrolet 235. I do
not have exact dates when the upgrades took place. The 871s retained the
S.A.E. size 3 mounting flange, the 1 3/16 main venturi, and the 1 9/16
throttle bore from the 745s. Upgrade changes: 871s -> 871sa - change in step-up valve cage and power
orifice 871sa-> 871sb - change in both the choke lever and shaft, and
the choke tube bracket 871sb-> 871sc - nozzle change Physical characteristics - (871sc) - casting numbers (871sc) -
throttle body 0-750 (A), bowl 0-533 (bowl casting number is inside); throttle
bore 1 9/16, tapers to 1 5/8.
The 2075s was introduced in 1954 on the Chevrolet 261 CID 6
cylinder. This unit retained the S.A.E. size 3 mounting flange, and the 1
3/16 main venturi from the 871s, but the throttle bore was enlarged to 1
11/16 inch. The 2075s has "BB-2" embossed on the throttle body,
instead of the "BB-1" embossed on the other BB-1 carburetors. 6A, 6A1 - I have no information on the Carter 6A, other than a
reference in a production index, so guessing there were issues with the first
production run, and it was superseded by the model 6A1. The model 6A1 was introduced in 1932 on the Chrysler 212 CID 6
cylinder in the Chrysler model CI. The carburetor has an S.A.E. mounting
flange size 2, with a 1 inch main venturi, and a 1 7/16 throttle bore. 6B1, 6B2 - The Carter 6B1 carburetor, introduced in mid-1932
superseded the model 6A1, with the only difference being the
throttle shaft and throttle lever. The 6B2 retained the physical aspects of
the 6B1; however, all calibrations including the idle jet, the main metering
jet, and the step-up jet all changed. The 6B1 and 6B2 were also used on
DeSoto. 6J2, 6J3 - The Carter model 6J2 was introduced in 1943 on
the Chrysler M-7 marine engine (250 CID) and the Chrysler M-8 marine engine
(323 CID). The 6J2 is an S.A.E mounting flange size 3, with a 1 1/16 inch
main venturi, and 1 1/2 inch throttle bore. The 6J3
superseded the 6J2 in 1946 on the M-7 engine only. Calibrations, including
main metering jet and step-up jet were changed, as was the fuel inlet valve. 6K1, 6K2, 6K3 - I have no surviving information on the model
6K1, other than a reference in a production index. The 6K2
was introduced on the Chrysler M-8 marine engine in 1946, replacing the use
of the 6J2 used on the engine in 1943. The 6K2 and 6K3 are the same physical
size as the 6J2 and 6J3, being an S.A.E. size 3 mounting flange, with a 1
1/16 inch venturi and 1 1/2 inch throttle bore. 6B, 6B1, 6B2 - There is no surviving data on the
model 6B other than a reference in a production index. As the Carter 6B1 is
basically the Chrysler 6A1 with a different throttle shaft, the 6B1 and 6B2
are discussed in the Chrysler section. 6C1, 6C2 - Carter Model 6C1 was introduced in 1940 on
the Dodge on models with T-88 and T-89 with 228 CID 6 cylinder engines. Both
6C1 and 6C2 are S.A.E. flange mounting size 3; both have 1 1/16
inch main venturii, and 1 7/16 inch throttle bore. The difference between the
2 carburetors is the throttle shaft and arm. Greatest difference in the 6C1,
6C2, 6D1, 6D1R, 6E1, and 6F1 are changes in throttle arms, choke brackets,
and choke valves; although the 6E1 is calibrated leaner than the others. 6D1, 6D1R - The Carter model 6D1, like the 6C1 and 6C2 was used
by Dodge in 1940, but only on the trucks with T-89 engines. The 6D1R was a
replacement carburetor introduced in 1940 replacing the 6C1, 6C2, and 6D1. The differences from the 6C1 and 6C2 to the 6D1 seem
to be only the choke tube bracket. Greatest difference in the 6C1, 6C2, 6D1,
6D1R, 6E1, and 6F1 are changes in throttle arms, choke brackets, and choke
valves; although the 6E1 is calibrated leaner than the others. As the 6D1R
was sold as a replacement, it came with a number of different linkage items
in the box, and the buyer was to install these items based on which
carburetor the 6D1R was replacing. 6E1 - The Carter 6E1 was used on the Dodge 228
CID 6 cylinder from 1940 through 1942 on trucks with engine models T-90,
T-91, T-128, T-130. Greatest difference in the 6C1, 6C2, 6D1, 6D1R, 6E1, and
6F1 are changes in throttle arms, choke brackets, and choke valves; although
the 6E1 is calibrated leaner than the others. 6F1 - The Carter 6F1 was used on the Dodge 228 CID 6
cylinder in 1941 and 1942 with engine models T-90, T-128, and T-130. Greatest
difference in the 6C1, 6C2, 6D1, 6D1R, 6E1, and 6F1 are changes in throttle
arms, choke brackets, and choke valves; although the 6E1 is
calibrated leaner than the others. 6M1 - The Carter 6M1 carburetor was used on Dodge 1948 and 1949
trucks with T-152 (236 CID) 6 cylinder engines, and T-154 (250 CID) 6
cylinders engines. The 6M1 has S.A.E. size 3 mounting
flange, 1 1/8 inch venturi, and 1 7/16 inch throttle bore. Later
models 6N1 and 6N2 were to be used as service replacements for the 6M1. 6N1, 6N2 - These models were used on Dodge trucks with the 236
CID, 250 CID, and 264 CID engines from 1950 through 1955.
They retained the same physical size of S.A.E. size 3 mounting flange, 1
1/8 inch main venturi, and 1 7/16 throttle bore as the 6M1. 257s - Carter 257s was used on Federal milk trucks models E3,
E4, and G-5 in 1933. This unit used a number 2 S.A.E. flange
mounting, a 1 inch venturi, and a 1 7/16 inch throttle bore. 257s was
calibrated richer than 262s. 262s - Carter 262s was used on Federal milk trucks model DM in
1933. This unit used a number 2 S.A.E. flange mounting, a 1 inch venturi, and a 1 7/16 inch throttle bore. 257s was calibrated richer
than 262s. 586s - Carter number 586s was original equipment on Gray Marine
4 cylinder 162 CID engines. The 586s has an S.A.E. size 2 flange mounting, a
15/6 inch venturi, and a 1 1/2 inch throttle bore. 638s - Carter number 638s was original equipment on Gray Marine
6 cylinder 226 CID engines. The 638s has an S.A.E. size 3 flange mounting,
a 1 1/16 inch venturi, and a 1 1/2 inch throttle bore. 640s - Carter number 640s was original
equipment on Gray Marine 4 cylinder 91 CID engines. The 640s has an S.A.E.
size 2 flange mounting, a 13/16 inch venturi, and a 1 1/2 inch
throttle bore. 2035s - Carter number 2035s was original equipment on Gray
Marine 4 cylinder 140 CID engines. The 2035s has an S.A.E.
size 2 flange mounting, a 1 1/16 inch venturi, and a 1 1/2 inch
throttle bore. 3377s - Carter number 3377s was original equipment on Gray
Marine 6 cylinder 226 CID engines. The 3377s has an S.A.E. size 3 flange
mounting, a 1 1/16 inch venturi, and a 1 1/2 inch throttle
bore. 3377s was superseded by Carter 4403s (Owens Marine). 2212s - Carter 2212s was original equipment on Lycoming-Spencer
industrial 2 cylinder 88 CID engines. The 2212s has an S.A.E. size 3 flange mounting, 1 3/16 inch venturi, and 1 11/16 inch throttle
bore. 641s - Carter 641s was original
equipment on Owens Yacht models 90 and 100. The 641s has an S.A.E. size 3
flange mounting. Carter 641s was superseded by Carter 4403s. 4403s - Carter 4403s was a marine replacement
model for both Gray Marine and Owens Marine. The 4403s superseded Carter
models 3377 (Gray Marine) and 641s (Owens Marine). Carter 4403s has an S.A.E.
size 3 flange mounting. 4A1, 4A2, 4A3 - There is no surviving data on
the Carter 4A1 other than a reference in a production index. Carter 4A2 and
4A3 were original equipment on 1932 Plymouth 4 cylinder 202 CID engines. Both
4A2 and 4A3 have S.A.E. size 2 flange mountings, a 1 inch venturi, and 1 7/16
inch throttle bore. The 4A3 was calibrated leaner on idle and richer on the
power circuit than the 4A2. COPIED FROM CARTER GENERAL BULLETIN NUMBER 33 DATED 22 APRIL
1932 "SUBJECT - BB 1 SPECIAL CARBURETOR Trade recognition of the BB carburetor, which appeared first on
the 1932 Chrysler 6 and DeSoto 6, and is now also on the Plymouth 6, has been
most enthusiastic. This is not surprising, in view of the superior design. Because of excellent performance, and the price, $12.00 less
$2.00 exchange allowance (less than half the cost of any unit of similar
construction), dealers and service stations in every section are installing
it on many motors other than those on which it is standard equipment, and in
many cases and in many cases are reporting excellent results, especially on
motors about the size of the Chrysler 6, such as the 1931 Chrysler 6, the
older Dodge 6 models, etc. We are told that the model will also fit without
the necessity of using an adapting flange, some models of Studebaker, Marmon,
Pontiac, Graham-Paige, Franklin, Peerless, Erskine, Nash, Willys-Knight, Reo,
and Durant. While we are not in the carburetor replacement business, we have
never complained because a distributor gave us a good volume business." As can be seen from the above quotation, the BB1-Special was the
first of the universal replacement BB1 carburetors, released in April 1932.
Because of size requirements, the BB1-Special was followed later in 1932 by
the 245s and the 289s. 245s, 245sa, 245sd - The Carter 245 series was the
smallest of the BB1 carbs designed for universal replacement use, having an
S.A.E. size 1 flange mounting, a 1 inch venturi, and 1 7/16 inch throttle
bore. The top casting was actually a size 2 casting, but drilled for size 1
mounting. The 245s came with a throttle arm riveted to the throttle shaft.
This was replaced on the 245sa with the adjustable arm. The bowl was changed
from cast iron to die-cast alloy on the 245sd. Early production die-cast
alloy bowls retained the float pin with screw plug. This was changed in
October 1945 to the internal float pin and slotted spring pin retainer. This
change was designated on the tags with "H-45". BB1-special, BB1A, BB1D - The BB1-special, BB1A, and BB1D were
the middle size of the BB1 carbs designed for universal
replacement use, having an S.A.E size 2 flange mounting, a 1 inch venturi,
and 1 7/16 throttle bore. Similar to the 245 series, the BB1-special had the
throttle arm riveted to the shaft, which was replaced by the adjustable arm
with the BB1A, and the bowl changed to die-cast alloy for the BB1D. Early
production die-cast alloy bowls retained the float pin with screw plug. This
was changed in October 1945 to the internal float pin and slotted spring pin
retainer. This change was designated on the tags with "H-45". 289s, 289sd - The 289s and 289sd were the largest of the
Carter BB1 carbs designed for universal replacement use, having an
S.A.E. size 3 mounting flange, a 1 1/16 inch venturi, and a 1 7/16 throttle
bore. However, the throttle bore was tapered toward the
flange mounting. The 289s had the cast iron bowl, which was replaced by the
die-cast alloy bowl on the 289sd. Early production die-cast alloy bowls
retained the float pin with screw plug. This was changed in October 1945 to
the internal float pin and slotted spring pin retainer. This change was
designated on the tags with "H-45". |
