DeSoto Carburetors for old Desoto's : DESOTO MODEL S8 1941 Previous | Home | Next

Form 64558—Canadian
DE SOTO E6N3-E6S3-EBI
March, 1941
Reprinted July, 1944
MOTOR SERIAL NUMBERS
E6N3—S8-100I to S8-3959
E6S3-EBI—S8-3960 and higher
E6N3-E6S3 used on cars with standard
drive and standard transmission.
EBI used on cars with fluid drive and
standard transmission.
Cut Shows E6S3 Carbureter
B-B DOWN-DRAFT CARBURETER—MODELS E6N3-E6S3, $29.40; EB I, $30.85
A $5.00 exchange allowance is deducted from the list price if buyer turns in the carbureter which is replaced by an E6N3, E6S3 or EBI.
CARBURETER SPECIFICATIONS
For De Soto Six Cylinder Engine: 3% Inch Bore, 4¼ Inch Stroke

DESOTO MODEL S8 1941

Dimensions: Flange size, It/2 inch (38.1 mm). Throttle bore, I-II/16 inch (42.86 mm). (E6N3) Main venturi, 1-9/32 inch (32.54 mm) I. D. (EBI-E6S3) Main venturi, I-11/32 inch (34.13 mm) I. D.
Float Setting: (EBI) Top of float 1/16" (1.58 mm) below top surface of carbureter body casting. (E6N3-E6S3) Top of float 5/64" (1.98 mm) below top surface of carbureter bode casting. (Plus or minus 1/64 inch (3.97 mm).
Vents: Outside, none. Inside balance vent .218 inch diameter (5.54 mm).
Gasoline Intake Needle: Triangular, horizontal. No. 44 (2.18 mm) drill in needle seat.
Idle Orifice Tube: (E6N3) Jet size, .0295 inch (.75 mm) drill. (EBI-E6S3) Jet size, .0276 inch (.70 mm) drill. Idle passage air bleed (in body) size .063 inch (1.60 mm) diameter. (E6N3) Economizer in body—size, .049 inch (1.25 mm) diameter. (EBI-E6S3) Economizer in body—size, .053 inch (1.35 mm) diameter.
Idle Ports: Upper port. Keyhole type; length, .128 inch (3.25 mm); width, .027 inch (.69 mm); .063 inch (1.60 mm) diameter hole at top. Top of port located .088 to .092 (2.24 to 2.34 mm) above top edge of valve. Lower port size, .053 to .057 inch (1.35 to 1.45 mm) drill. (For idle adjustment screw).
Set Idle Adjustment Screw: 1/2 to 11/2 turns open. For richer mixture turn screw out. Do not idle engine below 300 r.p.m. or 6 miles per hour.
Vacuum Spark Port: Slot (round end) type. Size, .040 by .110 inch (1.016 by 2.794 mm). Top of port .035 to .041 inch (.89 to 1.04 mm) above top edge of valve.
Main Metering Screw: (E6N3) Calibrated to flow 282 to 286 cc per minute.
(EBI-E6S3) Calibrated to flow 312 to 316 cc per minute.
(Do not gauge for size. If in doubt, replace with new part.)
Main Vent: Through diffuser (air bleed inside bowl), size..0315 inch (.80 mm) drill.
Main Vent Tube: Side holes:
2—.0354 inch (.90 mm), 21/64 inch (8.33 mm) from end. 2—.0354 inch (.90 mm), 1-1/64 inch (25.8 mm) from end.
Step-up Jet: (E6N3) Size, .0374 inch (.95 mm) drill. (EBI-E6S3) Size, .0413 inch (1.05 mm) drill.
Accelerating Pump: Type, delayed action. Stroke: Summer setting (inner hole, short stroke). Intermediate setting (center hole). Winter setting (outer hole, long stroke). Pump intake passage, size .115 to .120 inch (2.93 to 3.05 mm) diameter in body. Pump discharge passage: restriction (under ball check), size .062 to .065 inch (1.57 to 1.65 mm) diameter in body. Pump (discharge) jet size, .0374 inch (.95 mm) drill.
Pump Adjustment: 26/64 inch (10.32 mm) plunger travel; full throttle position, medium stroke. Use gauge T109-I17S.
Choke: Manual—Butterfly type, with pressure relief poppet valve. Interconnected to open throttle valve to fast idle position when choke is in use.
Slow Closing Throttle: (EBI) Dash pot with discharge (by-pass), size .0197 (.5 mm) drill, through plunger shaft.
Motor Tune-Up—Be Accurate! Always Use Feeler Gauges!
CAUTION: Change worn or leaky flange gaskets. Tighten manifold bolts and test compression before adjusting carbureter.
Spark Plug Gap .025"
Set
Breaker Points
.020"
Use Motor Gauge
Breaker Points to Open:
Top Dead Center
VALVE CLEARANCE
Set Valves (Hot) Intake .008" Exhaust .010"
Use Gauge
E6N3-S3—5/64 Inch
EBI—l/16 Inch
Idle Adjustment
Screw Setting
1/2 to 11/2
Turns Open
CARBURETER ADJUSTMENTS
If carbureter loads up after considerable service, check float level. Wear on lip of float lever will raise float level. Before adjusting float, be sure float lever pin is firmly seated. Reset float level by bending lip of float lever away from needle to raise level, or bend lip toward needle to lower float level. Bend vertical lip of float only.
If motor stalls while idling, set throttle lever adjusting screw so motor runs approximately 300 r. p. m. Then set idle adjustment screw to specifications. If these adjustments do not correct the trouble, remove idle orifice tube and plugassembly. Clean tube and passages with compressed air.
If acceleration is not satisfactory remove pump jet and clean with compressed air. However, it is usually advisable to replace the pump jet, as its cost is nominal. All jets must be seated gasoline tight. Poor acceleration may be due to damaged or worn nlunger leather in accelerating pump, sediment in pump cylinder or clogged intake ball check at bottom of pump cylinder and discharge ball check in discharge passage. If plunger is removed from cylinder, use care in installing to avoid damage to plunger leather.
Copyright 1941