What Did Nissan Used To Be Called

Alright, let's dive into a bit of Nissan's history. Many of you wrenching on older models might be curious about the company's origins and its original name. Understanding this context can sometimes even help when sourcing parts for classic Nissans. So, before Nissan became the global brand we know today, it went by a different moniker: Datsun.

The Origins of Datsun: From DAT to Nissan

The story begins with the DAT Motorcar Co. established in 1914. The name "DAT" was an acronym derived from the surnames of the company's initial investors: Kenjiro Den, Rokuro Aoyama, and Meitaro Takeuchi. DAT manufactured trucks and, in 1931, introduced a smaller car called the "Datson," meaning "Son of DAT." Later, the 'son' was changed to 'sun' because 'son' sounds like 'loss' in Japanese. Thus, Datsun was born. Nissan Jidosha Co., Ltd. eventually acquired DAT in 1934, and while the corporate name became Nissan, the Datsun name continued to be used on vehicles, particularly for export markets.

Purpose of Understanding Datsun's History

Why does any of this matter to us DIY mechanics? Well, knowledge of Nissan's past as Datsun is crucial when:

Sourcing Parts for Classic Models: Many parts catalogs for older vehicles will still list Datsun as the manufacturer. Knowing this helps you search using both names, increasing your chances of finding what you need.
Understanding Wiring Diagrams and Schematics: Older service manuals often refer to Datsun, not Nissan.
Troubleshooting: Familiarity with Datsun-era technology can provide valuable insights into the engineering principles behind older Nissan vehicles.

Key Specs and Main Parts (Focusing on a Datsun 240Z Example)

Let's take the Datsun 240Z as a prime example. This iconic sports car showcases the engineering of the Datsun era. Key specifications include:

Engine: L24 inline-six 2.4L (2393 cc) SOHC (Single Overhead Camshaft) gasoline engine. Understanding SOHC means the camshaft is located in the cylinder head, directly actuating the valves via rocker arms. This is a simpler valve train design compared to DOHC (Dual Overhead Camshaft) systems.
Transmission: Initially, a 4-speed manual transmission, later a 5-speed became available.
Fuel System: Twin Hitachi SU-type carburetors. These are constant depression carburetors, meaning they automatically adjust the fuel-air mixture based on engine demand.
Suspension: Independent front and rear suspension with MacPherson struts. MacPherson struts are a common suspension design combining the shock absorber and spring into a single unit.
Brakes: Front disc brakes, rear drum brakes.

Main parts of the Datsun 240Z, which would be vital to know for repairs, include:

Engine Block: The main housing for the engine's cylinders and other crucial components.
Cylinder Head: Contains the valves, camshaft, and spark plugs.
Carburetors: Meter the air and fuel mixture into the engine.
Distributor: Distributes the spark to the correct cylinder at the right time.
Radiator: Cools the engine coolant.
Suspension Components: Struts, springs, control arms, and bushings.
Brake Components: Calipers, rotors (front), drums (rear), brake lines, and master cylinder.

Understanding Wiring Diagrams (Example: Headlight Circuit)

Let's consider a simplified wiring diagram for a Datsun 240Z's headlight circuit. These diagrams use standardized symbols and line conventions.

Lines: Solid lines represent wires. Dashed lines might indicate a ground connection or a wire hidden within a harness. Different line thicknesses can sometimes indicate wire gauge (thicker lines = thicker wires, capable of carrying more current).
Colors: Each wire is assigned a color, indicated either with abbreviations (e.g., "BL" for Blue, "R" for Red) or full color names. Color coding is vital for identifying wires in a harness.
Symbols:
- Circle with an X: Represents a light bulb (headlight, taillight, etc.)
- Rectangle: Can represent a switch, relay, or fuse box.
- Triangle pointing down: Represents a ground connection (chassis ground).
- Coil Symbol: Represents a relay coil.
- Zigzag line: Represents a resistor.

How the Headlight Circuit Works: The circuit typically starts with the battery, then goes through a fuse (for protection), to the headlight switch. When the switch is turned on, it closes the circuit, allowing current to flow to the headlights. Some circuits use a relay to control the headlights, allowing a smaller current from the switch to control a larger current to the lights, improving switch longevity and headlight brightness. A proper ground connection is essential for the circuit to function correctly. A bad ground is a very common cause of electrical problems.

Real-World Use: Basic Troubleshooting Tips

Let's say your Datsun 240Z's headlights aren't working. Here's a basic troubleshooting approach:

Check the Fuses: A blown fuse is the most common culprit. Locate the fuse box (usually under the dashboard or in the engine bay) and check the fuse labeled "Headlights." Replace it with a fuse of the same amperage.
Test the Headlight Bulbs: Use a multimeter to check for continuity across the bulb's terminals. If there's no continuity, the bulb is blown.
Check the Headlight Switch: Use a multimeter to check if the switch is sending power when turned on.
Inspect the Wiring: Look for any damaged or corroded wires, especially near connectors. A visual inspection can often reveal obvious issues.
Check the Ground Connection: Ensure the headlight housings and other components have a good, clean ground connection to the chassis.

Safety: Highlighting Risky Components

When working on electrical systems, safety is paramount. Some components are particularly risky:

Battery: Disconnect the negative terminal before working on the electrical system to prevent shorts and potential fires.
High-Voltage Ignition System: The ignition coil can generate tens of thousands of volts. Avoid touching ignition components with the engine running.
Fuel System: When working on the fuel system, disconnect the battery and work in a well-ventilated area to avoid fuel vapors. Gasoline is highly flammable.

Always double-check your work and consult a service manual before starting any repairs.

Understanding the lineage of Nissan from its Datsun origins provides invaluable context when tackling repairs or modifications on older models. It allows you to navigate part catalogs, understand older diagrams, and appreciate the engineering that went into these classic machines.

We have detailed wiring diagrams and other technical information for many Datsun and early Nissan models. If you need specific diagrams, contact us, and we will see what we can provide.