ISO 8984-2:1993

Overview

ISO 8984-2:1993 defines standardized test methods for fuel injectors used in diesel (compression-ignition) engines. It applies to injectors requiring fuel delivery up to 300 mm3/(injection × cylinder) at full load and is intended for use with the hand-lever-operated testing and setting apparatus specified in ISO 8984-1. The part focuses on repeatable bench tests to assess injector performance and leakage characteristics under controlled conditions.

Key topics and requirements

• Scope and test apparatus

  • Tests are carried out using hand-lever-operated apparatus conforming to ISO 8984-1.
  • Calibration fluid shall conform to ISO 4113.
  • Operating fluid temperature: 23 °C ± 5 °C (seek manufacturer guidance if outside this range).
  • Injector-to-apparatus adaptor: specified by the injector manufacturer.

• Specified tests (may be performed as required by manufacturer)

  • Nozzle opening pressure - point at which fluid emits from the nozzle tip; monitor pressure rise and/or drop.
  • Chatter (atomization) - assessed by sound, visual observation of spray, and feel of the operating handle.
  • Spray pattern - observed by rapidly depressing the handle and compared to manufacturer specifications (do not assess during some other tests).
  • Seat leakage - after verifying nozzle opening pressure, raise pressure (typically to 2 MPa / 20 bar below recorded nozzle opening pressure), hold and check that no drops separate from the tip after 10 s. Additional rules apply for calibrating injectors per ISO 4008-3.
  • Back-leakage - flush injector, raise to a predetermined pressure PA, release handle and measure pressure decay time between Ps and Pc. Parameters PA/PB/PC and acceptable leakage rates reference ISO 4008-3; PA ≥ 0.5 MPa and Ps at least 2.5 MPa below nozzle opening pressure; PB and PC are referenced as 3 MPa (30 bar) where specified.

Practical applications and users

• Injector manufacturers: type approval, production QC and diagnostic procedures.
• OEMs and test laboratories: bench testing, component validation and supplier audits.
• Service and repair workshops: diagnostic bench checks and setting of injectors when matching manufacturer procedures.
• Regulatory/standards bodies and research organizations that require consistent, repeatable injector performance data.

Related standards

• ISO 8984-1: Hand-lever-operated testing and setting apparatus
• ISO 4113: Calibration fluid for diesel injection equipment
• ISO 4008-3: Fuel injection pump testing - application and test procedures
• ISO 7440-1: Calibrating nozzle and holder assemblies

Keywords: ISO 8984-2:1993, diesel engines, fuel injector testing, nozzle opening pressure, chatter, spray pattern, seat leakage, back-leakage, hand-lever-operated testing.