DeSoto Carburetors for old Desoto's : DESOTO MODEL S8 1941

Form 6475C—Canadian
DE SOTO E6U I -E6U2
February, 1941
Reprinted August, 1946
Cut Shows E6U2 Carbureter

DESOTO MODEL S8 1941

(Superseded by E6U2R)
MOTOR SERIAL NUMBERS E6U I -E6U2—4200 and higher
(Fluid Drive & Simplimatic Transmission)
BB-Downdraft Models E6U I, List Price $32.35; E6U2, List Price $35.30
Exchange Allowance E6U I, $5.00; E6U2, $7.50
CARBURETER SPECIFICATIONS
For DeSoto Six Cylinder Engine: 3%" Bore, 41/4" Stroke
Dimensions: Flange size, 11/2 inch S.A.E. Throttle bore, 1-1 1/16 inch (42.86 mm).
Main venturi, I-I I/32 inch (34.13 mm) I. D.
Float Setting: Top of float 5/64 inch (1.98 mm) plus or minus 1/64 inch (.397 mm) below top surface of carbureter body casting.
Vents: Outside, none. Inside balance vent .218 inch diameier
(5.54 mm).
Gasoline Intake Needle: Triangular, horizontal. No. 44 (2.18
mm) drill in needle seat.
Idle Orifice Tube: Jet size, .0276 inch (.70 mm) drill. Idle passage air bleed (in body), size .063 inch (1.60 mm) diameter. Economizer in body, size .053 inch (1.346 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 inch (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.
Main Metering Jet: 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.
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 Jot: 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 ball check seat size .115 to .120 inch (2.93 +o 3.05 mm) diameter in body. Pump discharge passage restriction (under ball check), size .062 to .065 inch (1.58 to 1.65 mm) diameter in body. Pump (discharge) jet, size .0374 inch (.95 mm) drill.
Pump Adjustment: 26/64 inch plunger travel; full throttle position, medium stroke. Use gauge TI09-117S.

Choke: Manual—butterfly type with pressure relief valve, inter-connected to open throttle valve to fast idle position when choke is used.
Slow Closing Throttle: (E6U I) Dash pot with discharge (by-pass). Size .0197 (.5 mm) drill, through plunger shaft. (E6U2) (With magnetic coil assembly) Dash pot with discharge (by-pass). Size .0197 inch (.5 mm) drill through valve cage.

Vacuum Spark Port: Slot (round end) type: Size .040 by .110 inch (1.016 by 2.794 mm). Top of port .052 to .058 inch (1.32 to 1.47 mm) above top edge of valve.
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 Set
Plug Gap Breaker Points
.025" .020"
Use Gauge 5/64 Inch
Use Motor Gauge
Breaker Points to Open:
Top Dead Center
VALVE CLEARANCE
Set Valves (Hot) Intake .008" Exhaust .010"
Idle Adjustment
Screw Setting
V2 to 1 i2
Turns Open
Copyright 1941