Nissan Z24I 2.4L L4 Remanufactured Engine – 4/85-8/89

Description

Prevent twin-spark plug fouling and stop oil control ring sticking under 137 lb-ft continuous pulling torque during grueling municipal courier routes without power fade through the Nissan Z24I TBI Remanufactured Engine. Machined for 4/85 to 8/89 D21 Hardbody and Pathfinder platforms, this throttle-body injected four-cylinder engine delivers rugged pulling power across heavy utility fleet tasks.

Cast-iron block metallurgy provides dependable wear resistance and incorporates an Ra 28 micro-inch deck surface finish. A precision-machined forged steel crankshaft rotates on tri-metal journal bearings, driving forged steel connecting rods and hypereutectic pistons with anti-friction skirt coatings. Sump capacity measures 4.5 quarts in a stamped steel oil pan, while high-velocity oil passages protect valvetrain components across an overall dry engine mass of 310 lbs.

Key Features of Nissan Z24I TBI

Fleet maintenance supervisors buy Nissan Z24I TBI remanufactured engine packages to eliminate roadside service interruptions across demanding regional routes. Precision line-honed journals minimize internal drag to optimize sustained highway pulling power.

• Dual-spark cylinder head architecture enhances combustion speed for consistent low-end torque
• Single overhead camshaft operates eight valves via durable mechanical rocker arm assemblies
• Multi-layer steel cylinder head gaskets maintain combustion seals against continuous thermal cycles
• Plateau diamond honed cylinder bores eliminate ring blow-by and stabilize oil retention
• High-flow internal trochoid oil pump provides 50 PSI cruising lubrication to protected bearings
• Induction-hardened valve seat inserts resist wear under prolonged continuous fleet operation
• Nissan Z24I TBI long block units pass rigid non-destructive ultrasonic flaw testing

Torque Output Operational Limits

This motor outputs 106 horsepower at 4800 RPM alongside 137 lb-ft continuous torque at 2400 RPM using an 8.3:1 compression ratio. Dynamic cylinder cranking compression tests between 160 and 175 PSI across all four cylinders. Normal coolant operating temperatures hold between 180°F and 195°F, backed by 16 PSI hot idle oil pressure and 50 PSI cruising pressure. Radiator thermal rejection capacity measures 2350 BTU per minute under Severe Commercial Fleet duty cycle standards.

Crankshaft Flange Alignment Geometry

The rear crankshaft flange uses a six-bolt flywheel mounting pattern with an engineered 0.826-inch pilot counterbore diameter. Front crankshaft snout measures 1.023 inches with a machined Woodruff keyway slot for timing sprocket retention. Dial indicators measure crankshaft axial thrust endplay between 0.003 and 0.007 inches across all finished builds.

Break-In Protocol Servicing Rules

Technicians must prime internal engine oil passages with an external pressure tank before turning the ignition key to protect fresh bearing surfaces from dry friction. Conduct a twenty-minute cam run-in procedure at 2000 RPM using high-zinc break-in lubricant. This engine is not engineered for aftermarket turbochargers, nitrous systems, or trailer towing weights exceeding vehicle chassis ratings.

• Inspect fluid reservoirs and accessory belts each shift
• Change motor oil and replace spin-on filter every 3500 miles
• Inspect timing chain tensioner and guides every twelve months

Fleet Guarantee Package Manifest

Supported by our 3-Year 100000-Mile commercial fleet warranty for verified transport operations. The heavy wooden container holds the remanufactured long block engine, high-capacity oil pump, complete engine install gasket kit, spark plug tube seals, and a certified dynamometer qualification inspection report.