Featuring an exact 2389cc displacement, this Nissan D21 Z24I Remanufactured Engine features dual-spark cylinder head casting 10W and block casting Z24 metallurgy. Machinists line-hone cast iron blocks and micro-polish crankshaft journals. Technicians must conduct complete cooling system vacuum bleeding and execute an exact 500-mile break-in oil change to protect the single overhead camshaft from excessive lobe wear.

Cast with iron block markings Z24 and 10W, this engine features a left rear dipstick hole location and rigid parent-metal cylinder bores. The rotating assembly features a micro-polished forged steel crankshaft casting 30W, forged connecting rods, and oversized hypereutectic pistons. SOHC 8-spark-plug cylinder head casting 10W receives diamond deck resurfacing for head gasket sealing. Dry weight equals 240 lbs within crated dimensions of 36in length by 36in width by 36in height. Sump capacity measures 4.3 quarts.

Key Features of Nissan Z24I

Commercial fleet managers buy Nissan Z24I remanufactured engine long blocks to restore work truck hauling power and eliminate dual-ignition misfire issues. This long block replacement provides verified machine shop tolerances for vintage rear-wheel-drive and 4-wheel-drive trucks.

- Pre-installed front timing cover, oil pump, and distributor drive gear reduce garage installation labor hours.
- Dual-spark SOHC cylinder head casting 10W provides complete combustion across 2 spark plugs per cylinder.
- Block casting Z24 features the correct left rear dipstick location for truck oil pan clearance.
- Crankshaft casting 30W journals receive micro-polishing to hold total indicator runout under 0.0003in TIR.
- Diamond plateau honed cylinder walls establish an Ra 16 micro-inch finish for rapid ring seating.
- Align-honed cast iron main saddles support smooth crankshaft rotation under heavy truck payloads.
- Multi-layer composite cylinder head gaskets prevent combustion gas blow-by across cast iron block decks.

Dyno Bench Clearance Machining Specifications

Dyno cell testing validates mechanical oil gallery pressurization and low-RPM shaft torque output before packaging. The 2.4L 2389cc SOHC engine outputs 106 HP at 4,800 RPM and 137 ft-lbs of shaft torque at 2,400 RPM. Main journal oil clearance holds between 0.0011in and 0.0015in, while connecting rod clearance measures 0.0012in. Individual cylinder compression gauges verify 175 PSI across all 4 cylinders. Hot engine oil pressure maintains 55 PSI at 3,000 RPM with regulated coolant temperatures steady at 190°F.

Vehicle Fitment Drivetrain Guide

This long block fits 1986 Nissan 720, 1986 to 1989 Nissan D21 Hardbody, 1987 to 1988 Nissan Pathfinder, and 1987 to 1988 Nissan Van models equipped with the fuel-injected 2.4L 2389cc Z24I engine and left rear dipstick. Drivetrains include rear-wheel drive and 4-wheel drive. This unit does not fit carbureted Z24 engines requiring casting 324A or later 12-Valve KA24E trucks due to intake manifold, timing cover, and cylinder head architecture differences.

Installation Protocol Service Requirements

Technicians must synchronize dual ignition coils, verify distributor drive spindle engagement, and burp cooling air pockets during installation. Operating warnings explicitly ban installation in custom turbo conversions exceeding 5 PSI boost or heavy-duty motorhomes exceeding vehicle gross chassis ratings.

- Pre-fill the spin-on oil filter and prime engine lubrication passages with 10W-30 conventional motor oil.
- Drain initial break-in oil and install a replacement oil filter at the 500-mile service point.
- Check mechanical valve lash clearances on intake and exhaust rockers at the 1,500-mile service mark.

Warranty Terms Core Return Policy

This long block carries our standard 3-Year Unlimited-Mile warranty for dependable road service. We provide free prepaid return freight shipping for your depleted rebuildable core engine within a 30-day window. The crated package contains the remanufactured long block, pre-installed timing cover, oil pump, distributor drive, and oil pan.