1972 510 & Pickup Engine Modification: Description

NOTE: Air Injection is not used with this system.

The system consists of a temperature sensing switch, a throttle switch, a gear switch (Manual Trans.), a speed switch (Auto. Trans.), a relay, and a dual-point distributor. Timing is retarded when the following conditions are present:

Temperature inside the passenger compartment is above 50°F.
The carburetor throttle valve is opened 3°-30° (510 with manual transmission), 3°-35° (510 with automatic transmission), or 3°-40° (521 with manual transmission).
Shift lever is in third gear position (manual trans.), or car speed is above 13 MPH (auto, trans.).

Fig 1: 521 Pickup Emission Control System (Manual Trans.)
Courtesy of NISSAN NORTH AMERICA, INC.

Fig 2: 510 Sedan & Wagon Emission Control System (Manual Trans.)
Courtesy of NISSAN NORTH AMERICA, INC.

NOTE: On the 527 the combination throttle switch is replaced with separate throttle switch on carburetor, and an accelerator switch by the accelerator pedal.

In conjunction with, but separate from, the dual point transmission controlled spark system, the 510 and 521 vehicles employ an automatic temperature control air cleaner, an electric automatic choke and a boost controlled deceleration device.

Fig 3: 510 Sedan & Wagon Emission Control System (Auto. Trans.)

Courtesy of NISSAN NORTH AMERICA, INC.