Hitachi DCx carburetors have different specifications depending on market, year, state and other factors. All A-series engines used Hitachi DCx-306 carburetors 26/30 bores, except for the A10 engine which used a smaller DCG-286 model with 26/28 bores. A12 carburetors have 20/26 primary/secondary venturis, and other engines used bigger venturis up to A15s which have bigger 21/27 or 23/27 venturis.
- DCG - manual choke
- DCH - electric automatic choke
Instruction Sheet
Hitachi DCH306 ID boss
Hitachi DCH306
North American Models
Carburator Models
Year | Engine | Hitachi Model
|
1971 | A12 | Hitachi DCG306
|
72-73 | A12 | Hitachi DCH306
|
74 | A13 | Hitachi DCH306
|
75-76 | A14 | Hitachi DCH306
|
Primary Main Jet - North American Models
Year | Jet Size
|
1971 | No. 98
|
1972 | No. 97
|
1973 | No. 95
|
1974 | No. 104
|
1975-76 California | No. 104
|
1975-76 | No. 102
|
1977-78 California Manual Trans. | No. 105
|
1977 | No. 104
|
1978 California Manual Trans. | No. 105
|
1978 | No. 104
|
1978 Federal | 5-speed No. 107
|
Main Air Bleed
71-73 No. 80
|
74 No. 65
|
75-77 No. 95
|
1978 All California No. 95
|
1978 Four-speed No. 110
|
1978 Five-speed No. 65
|
1978 Automatic No. 95
|
Secondary Main Jet
Year | Jet Size
|
1971 | No. 135
|
1972-73 | No. 140
|
1974 | No. 145
|
1975 | No. 150
|
1976 | No. 145
|
1977-78 | No. 145
|
Secondary Air Bleed
Year | Jet Size
|
71-78 | No. 80
|
1977 California 5-speed | No. 60
|
Primary Slow Jet
Year | Jet Size
|
1971-74 | No. 43
|
1975-78 | No. 45
|
1978 non-California 5-speed | No. 46
|
Secondary Slow Jet
Year | Hitachi Model
|
71-76 | No. 50
|
Australia Model Specifications
Hitachi DCG-306 (G indicated manual choke)
NOTE: B310 A15 uses DCF-306, which differs from DCG as follows:
* vacuum secondaries, instead of counterweighted secondaries
* replaceable sight glass with O-ring
* modified choke fast idle system
Datsun B310 (source: Gregory's)
Controls
Idle Cut Off Solenoid (anti-diesel valve)
Servo Diaphragm
Dashpot
Venturi
primary, A12: 20 mm
primary, A14: 22 mm
primary, A15: 21 mm
secondary, A12: 26 mm
secondary, A14/A15: 27 mm
Main jet,
primary, A12: 96
primary, A14: 104
primary, A15: 100
secondary, A12: 150
secondary, A14: 150
secondary, A15: 145
Main air bleed
primary, A12: 80
primary, A14: 65
primary, A15: 70
secondary, A12: 80
secondary, A14: 60
secondary, A15: 80
Slow Jet
primary, A12: 43
primary, A14: 46
primary, A15: 43
secondary, A12: 50
secondary, A14: 50
secondary, A15: 70
Slow air bleed
primary, A12: 220
primary, A14: 170
primary, A15: 100
secondary, A12: 100
secondary, A14: 100
secondary, A15: 100
Power jet
A12: 60
A14: 60
A15: 40
Japan Market Specfications