On Vehicle Adjustments: Reassembly

To reassemble, reverse disassembly procedure. Prevent primary and secondary circuit parts from becoming mixed. When installing choke housing, carefully fit choke shaft lever to bimetallic spring. Close choke valve and pull on diaphragm shaft to ensure that choke closes properly.

Fig 1: Carburetor Jet & Air Bleed Locations

Courtesy of NOT AVAILABLE

Fig 2: Exploded View of Hitachi 4-Barrel Carburetor

Courtesy of NOT AVAILABLE

1978 CARBURETOR ADJUSTMENT SPECIFICATIONS

Application

Idle Speed (Engine RPM)

Float Level Setting In. (mm)

Float Drop Setting In. (mm)

Choke Linkage (Off Car) In. (mm)

Accelerator Pump Volume ⁽¹⁾

Choke Valve Opening ⁽²⁾ In. (mm)

Hot

Fast

RX-4 & Cosmo

750±25

3000-3500

.45.49 (11.5-12.5)

2.11-2.15 (53.5-54.5)

.067.079 (1.7-2.0)

6.8-9.2

.169.185 (4.3-4.7)

⁽¹⁾	Measured in cubic centimeters (cc). Amount of fuel that should have been drawn from container (burette) in 10 strokes.

⁽²⁾	Measured between stopper and bimetal spring lever.

1979 CARBURETOR ADJUSTMENT SPECIFICATIONS

Application

Idle Speed (Engine RPM)

Float Level Setting In. (mm)

Float Drop Setting In. (mm)

Choke Linkage (Off Car) In. (mm)

Accelerator Cable Free Play

Choke Valve Opening ⁽²⁾ In. (mm)

Hot

Fast

RX-7

750±25

⁽¹⁾

.61-.65" (11-21)

1.8-2.2" (46-56)

.035-.040" ⁽²⁾ (0.9-1.1) ⁽²⁾

.04-.12" (1-3)

⁽³⁾

⁽¹⁾	Manufacturer does not supply fast idle speed. See Choke Linkage (Fast Idle Opening Angle).

⁽²⁾	Federal clearance. California vehicles should have.051-.059" (1.3-1.5 mm) clearance.

⁽³⁾	Varies with ambient temperature. See Figure.