ROCHESTER CARBURETORS

Bulletin 9C-330 15 December 1957

BULLETIN 9C-330 PAGE 4 OF 4
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SETTING .015" - TOOL BT-91A
With the choke valve partially closed, there should be a clearance of .015" between the lockout lever and the fast idle cam, to allow free movement of the cam when the secondary throttle valves are closed. To adjust, bend with Tool BT-18 or Tool BT-91A.
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SETTING .043", GAUGE BT-131
With the idle screw resting on the second step of the fast idle cam and against the shoulder of the high step, bend the choke rod with Bending Tool BT-18 to obtain sufficient clear­ance to allow the insertion of the correct gauge between the upper edge of the choke valve and the dividing wall of the air horn.
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SETTING .015" - TOOL BT-91A
With the choke valve fully open and the secondary throttle valves partly open, there should be sufficient clearance between the lockout lever and the fast idle cam to allow free movement of the secondary valve shaft. Adjust with Bending Tool BT-91A to the specification listed below.
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SETTING .235", GAUGE BT-131
Bend the unloader tang with Bending Tool BT-69 as necessary to allow the insertion of the proper gauge between the upper edge of the choke valve and the dividing wall of the air horn, with the throttle valves wide open.
QUICK REFERENCE SPECIFICATIONS
Carburetor No.
1957 Early—7009846 1957 Late—7012126
1958
1957-1958
Tune-up Specifications
7012128—P.G.
701 1108 Turbo-Glide
PRIM.
SECONDARY
PRIM.
SECONDARY
PRIM.
SECONDARY
SPARK PLUG GAP—.035" BREAKER POINT GAP—.016" CAM DWELL—28° - 32°
IGNITION TIMING — 4 BTDC AT IDLE
IDLE R.P.M, POWERGLIDE—425 IN DRIVE SYNCHROMESH—475 NEUTRAL
GAUGE No.
BORE
1-5/16"
1-5/16"
1-5/16"
1-5/16"
1-7/16"
1-7/16"
SMALL VENTURI
1/4"
1/4"
1/4"
1/4"
1/4"
1/4"
LARGE VENTURI
1"
1-1/16"
1"
1-1/16"
1-1/8"
1-1/4"
MAIN METERING JETS
.048
.051
.048
.052
.058
.065
IDLE NEEDLE HOLES
.046
—
.046
—
.046
—
SEC. LOWER
.038
—
.030
—
.035
—
DISCHARGE MIDDLE
.027
—
.027
—
.026
—
HOLES UPPER
.028
—
.028
—
.026
—
SPARK DRILLINGS
(4) .052
—
(4) .052
(4) .052
—
PUMP JETS
(4) .026
—
(4) .026
—
(4) .026
—
POWER RESTRICTIONS
.037
—
.038
—
.057
—
CHOKE CHANNEL
.098
—
.098
—
.089
—
RESTRICTIONS BY-PASS
—
—
—
—
—
—
IDLE TUBE RESTRICTIONS
.027
—
.027
.033
—
LOWER IDLE BLEED
.033
—
.033
—
.048
—
Adjustments
DIMENSION
DIMENSION
DIMENSION
1957
1958
PRIM. SEC.
FLOAT LEVEL
1-5/8"
1-11/16"
1-5/8"
1-11/16"
BT-89
BT-89 BT-143
FLOAT DROP
2-1/4"
2-1/4"
2-1/4"
2-1/4"
BT-93 or Scale
BT-93 or Scale
PUMP ROD
1-1/16"
1-1/16"
—
1-1/16"
—
BT-195 or Scale
BT-145 or Scale
IDLE VENT
—
31/32"
31/32"
—
—
BT-145 or Scale
AUTOMATIC CHOKE
1 NOTCH LEAN
1 N. L.
—
INDEX
—
—
__
CHOKE ROD
.043
.043
.043
—
BT-131
BT-131
UNLOADER
.235
.235
—
.235
__
BT-131
BT-131
SECONDARY LOCKOUT
.015
.015
—
.015
—
Feeler Gauge
Feeler Gauge
SECONDARY CONTOUR
.015
.015
—
315
—
Feeler Gauge
Feeler Gauge
FORM NO. 1258 I.P.S. PRINTED IN U.S.A.
SPECIAL TOOLS SHOWN IN THESE PICTURES ARE AVAILABLE THROUGH UNITED MOTORS SERVICE DISTRIBUTORS

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