RCB 9C-326

BULLETIN 9C-326

PAGE 4 OF 4

SETTING: .089" -GAUGE, BT-108

SETTING: .360"-GAUGE, BT-I08

With the throttle valves held wide open, the choke valve should be open just enough to admit the large end of Gauge BT-108, Dimension .360", between the upper edge of the choke valve and the inner air horn wall. To adjust, bent the tang on the throttle lever as shown with Bending Tool BT-69.

Turn the idle screw in until it just contacts the second step of the fast idle cam. With the screw resting on the second step and against the high step, bend the choke lever tang with Tool BT-69 as necessary to admit the small end of the gauge between the upper edge of the choke valve and the air horn wall


		QUICK REFERENCE SPECIFICATIONS
CARBURETOR No.		7012133	7012451	7012452	1958 TUNE-UP SPECS.
BORE		1-7/16"	1-7/16"	1-7/16"
SMALL VENTURI		1/8"	1/8"	1/8'
LARGE VENTURI		1-3/32"	1-3/32"	1-3/32"	SPARK PLUG GAP—.035
MAIN METERING JETS		.053	.056	.056	BREAKER POINT GAP—.016
IDLE NEEDLE HOLES		.040	.040	.040	BREAKER POINT GAP—.016
SEC. DISCHARGE	LOWER	.028	.031	.031	CAM DWELL—30°
	MIDDLE	.026	.026	.026	IGNITION TIMING—4°BTDC at Idle
HOLES	UPPER	.032	.028	.028	IDLE R.P.M. AUTO. TRANS.—425 R.P.M. "DR" SYNCHROMESH—475 R.P.M. "Neut"
SPARK DRILLINGS		(2).040	(2).040	{2).040
PUMP JETS		.026	.026	.026
POWER RESTRICTIONS		.039	.039	.038
CHOKE RESTRICTIONS	CHANNEL	.089	.089	.089
CHOKE RESTRICTIONS	BY-PASS	.040	.040	.040
IDLE TUBE RESTRICTIONS		.030	.027	.029
ADJUSTMENTS		DIMENSIONS			GAUGE No.
FLOAT LEVEL		1-19/64"	1-19/64"	1-19/64"	BT-144
FLOAT DROP		1-29/32"	1-29/32"	1-29/32"	BT-144
PUMP ROD		57/64"	57/64"	57/64"	BT-144
IDLE VENT			49/64"	49/64"	BT-144
AUTOMATIC CHOKE		INDEX	INDEX	INDEX
CHOKE ROD		.089	.089	.089	BT-108
UNLOADER		.360	.360	.360	BT-108

CARBURETOR TOOLS AND GAUGES AS LISTED ARE AVAILABLE THROUGH UMS DISTRIBUTORS

Rochester Carburetor

A GENERAL MOTORS PRODUCT — A UNITED MOTORS LINE

FORM 1254 I.P.S.

PRINTED IN U.S.A.