Bulletin 9D-7
August,
1951
Model "BB"
Page 9
ROCHESTER PRODUCTS, DIVISION OF GENERAL MOTORS,
ROCHESTER, NEW YORK
DISASSEMBLY OF MODEL "BB" CARBURETOR
CHOKE DISASSEMBLY
1. Loosen 1/2" brass fitting on choke
suction tube
2. Remove three attaching choke cover screws
and retainers, then remove choke cover, Cover Gasket, and Thermostatic Coil assembly
from choke housing,
3. Remove Baffle plate.
4. Remove cotter pins from each end of choke
rod and remove rod.
5. Remove retaining screw at end of choke shaft
and carefully pry off choke trip lever, spacing washer, and choke counter
weight.
6. Remove two choke valve screws and then
remove choke valve.
7. Rotate choke shaft counter clockwise to
free choke piston from housing and then remove piston and choke shaft from
carburetor.
8. Remove choke piston pin and piston from
choke shaft.
9. Remove two choke housing attaching screws.
Choke housing and gasket may now be removed from Air Horn.
AIR HORN
1. Remove filter screen retainer nut and gasket
with 3/4"
wrench and
remove filter screen.
2. Remove clip on upper end of pump rod and
cotter pin on bottom. Remove pump rod from rocker arm.
3. Remove cotter pins from center and end of
rocker arm and remove rocker arm and spacing washer from Air
Horn.
4. With carburetor upended on a flat surface,
remove four Air Horn screws.
5. With carburetor again in an upright
position, remove remaining four Air Horn screws and
lift Air Horn gently from bowl. (If
necessary, lightly tap sides of Air Horn to break the
gasket seal.)
6. Place Air Horn upended on a flat surface.
Remove float hinge pin and lift float assembly from Air Horn.
7. Press rubber seal on pump plunger arm
through Air Horn and remove both the seal and the pump plunger. Then separate pump plunger
and the rubber seal.
8. Remove float needle seat and gasket with a
1/2" bit screwdriver.
9. Remove main metering jets from main well
support.
NOTE: It is not
necessary to remove power valve assembly.
10. Loosen two screws and remove main well
support. Air Horn gasket may now be removed.
11. Remove power piston and actuating
spring.
12. Loosen screw and remove secondary venturii
cluster.
13. Carefully remove float balance spring and
clips.
14. Remove retaining clip and pump vent disc from
Air Horn.