The 2.4-liter engine used in the 1986 Nissan D21 (Hardbody) is the Nissan Z24 family, with the fuel-injected variant commonly referred to as the Z24i.
Background: the D21 and its powertrains
The D21 Hardbody, introduced in 1986, offered a range of inline-four engines designed to balance capability with reliability. Among the options available in various markets was a 2.4-liter unit, which earned its own designation within Nissan’s engine lineup. Understanding these names helps when researching manuals, parts, and compatibility for restoration or maintenance.
The 2.4 L engine family in the D21
In Nissan nomenclature, the 2.4 L inline-four is part of the Z-series. The early carbureted 2.4 L engines were grouped under the Z24 name, while later, fuel-injected versions carried the Z24i designation. These designations were used across Nissan trucks and SUVs of the era, including the D21 lineup.
Before listing the main variants, it’s helpful to know the general distinction between them. The following variants represent the core 2.4 L options found in the D21 and related models from that period.
- Z24 — 2.4 L inline-four, carbureted configuration used in early D21 trucks and other Nissan applications.
- Z24i — 2.4 L inline-four with fuel injection (EFI), a later upgrade that improved efficiency and performance.
Concluding the overview, the two primary labels you’ll encounter for the 2.4 L D21 engine are Z24 (carbureted) and Z24i (fuel-injected). These reflect the basic evolutionary path of the engine during the D21’s production run and help pinpoint parts, service manuals, and swap compatibility.
Additional context: significance for owners and restorers
Identifying whether a D21 uses the Z24 or Z24i informs maintenance parts (carburetor vs. EFI components, intake manifolds, sensors, and fuel systems), service intervals, and potential compatibility with aftermarket upgrades. Verified engine codes on the valve cover or in theVIN/owner’s manual can confirm which variant is installed.
Summary
The 2.4 L engine powering the 1986 Nissan D21 is the Z24 family, with the standard carbureted version labeled Z24 and the later fuel-injected variant known as Z24i. This naming reflects Nissan’s broader Z-series engine lineup of that era and is a key detail for identification, maintenance, and restoration of D21 pickups.