Subject: Revised (AFB 3269S) Carburetors
Model and Year: 1962 Corvettes with RPOs 396 and 583
Source: Service and Mechanical Department, Product Engineering Technical Information, 1962 Product Data Book
Date: May 11, 1962
Several design revisions have been incorporated in the Carter (AFB 3269S) Carburetor, Part No. 3797699, used in high-performance 327 cu. in. engines for 1962 Corvette Models (RPO 396 and 583) and 1962 Passenger Cars (RPO 397). Revised carburetors may be identified by a change letter stamped on the throttle body flange preceding the date stamp. Successive revisions incorporate all previous changes. For example "C" revision includes "A" and "B" etc.
To reduce the tendency to stall on brake stops and/or closed throttle turns, the primary clusters and metering rods were changed effective 10-4-61. This revision was identified with the letter "A". To correct for repeat stalling on vehicles built prior to this change, proceed as follows:
Up thru revision "A", Carburetor Assembly #3797699 was used on Automatic transmission equipped units as well as manual transmission equipped units. On 11-3-62, common usage was discountinued and Carburetor Assembly, Part No. 3819207 was effective in Production on vehicles equipped with Powerglide transmissions. This was the same basic carburetor with revision "A" included.
Simultaneous and to correct for an over-rich condition and hard starting on 3 or 4-speed transmission equipped vehicles, the choke setting was changed from index to one notch lean and choke valve opening at full choke increased from .078" to .092". This revision on Carburetor #3797699 was identified with the letter "B". If this hard starting condition is experienced on earlier units, re-adjust choke to these later specifications.
Then effective 2-15-62, Carburetor #3797699 for 3 or 4-sp. transmission equipped vehicles, was revised to enrich the air fuel mixture at wide open throttle. This revision, identified by letter "C", included new metering rods and secondary jets and was incorporated to prevent possible engine failures due to detonation or preignition.
On units repeatedly engaged in competitive operations, the late design metering rods and jets should be installed.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
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Article ID: 163
Created: July 13, 2014
Last Updated: June 8, 2015
Online URL: https://www.corvetteactioncenter.com/tech/knowledgebase/article/1962-corvette-technical-information-carter-afb-carburetor-revisions-163.html