More information is needed. Which 1974 Datsun, and which motor? The make, and model of the car, as well as the numbers of cylinders are needed, total displacement of the engine would also be helpful.
The datsun pickup across that year, the datsun 240/260 series cars, and several others had substantially different engines and distributors.
1 - 4 - 3 - 2
The firing order should be 1-8-4-3-6-5-7-2.
The firing order is 18436572.
1 - 5 - 4 - 2 - 6 - 3 - 7 - 8 The distributor rotor turns COUNTERCLOCKWISE
It's imprinted on the engine block near the distributor just below the top of the block.
1 - 5 - 3 - 6 - 2 - 4 The distributor rotor turns CLOCKWISE
1-3-7-2-6-5-4-8 Rotor turns counterclockwise.
The firing order of a 1974 Chevy 350 is 1-8-4-3-6-5-7-2
Check the coil, rotor, condenser, distributor cap, and coil wire.
The distributor cap order for a Chevy 283 varies depending on the year of the motor. A 1975 to 1991 has the number one cylinder at the top just to the left of center. The 1967 to 1974 distributor has the number one cylinder at the top just to the right of center. The firing order is 1, 8, 4, 3, 6, 5, 7, 2.
A 1974 Thunderbird with a 460 cu. in. engine firing order is 1 5 4 2 6 3 7 8
18436572