ISO 4008-3:1987

Overview

ISO 4008-3:1987 - "Road vehicles - Fuel injection pump testing - Part 3: Application and test procedures" is a workshop-level procedural supplement to ISO 4008 Parts 1 and 2. It coordinates the detailed technical requirements from the other parts and referenced standards with practical procedural instructions needed to apply, validate and document fuel injection pump tests for compression‑ignition (diesel) engines.

Key topics and requirements

• Scope and purpose: Provides mandatory test conditions, recommended practices and procedural instructions for conducting ISO-conforming injection pump tests in workshops and test facilities.
• Test schedules and content: Defines the minimum information a test schedule must contain (pump identity, test type, injectors, high‑pressure pipe details, mounting, test speeds, test numbers, direction of rotation, peak pressure if >625 bar, warming/stabilization procedures, delivery values, tolerances).
• Equipment conformity: Test benches, measuring systems and high‑pressure pipes must carry manufacturer conformity documentation and ISO identification (see ISO 4008‑1 and ISO 4093 references). Test benches are to be supplied with operation/maintenance instructions and characteristic graphs.
• Calibration fluid: ISO 4113 calibration fluid is specified for ISO tests. Temperature must be maintained at 40 ± 2 °C and viscosity monitored weekly; fluid must not be used if viscosity at 40 °C exceeds 3.0 mm2/s or if it has been exposed to < −10 °C without manufacturer advice.
• Test injectors and maintenance: Calibrating injectors must be documented; maintenance and usage records are required. Annex B contains mandatory maintenance for calibrating injectors.
• High‑pressure pipes care: Pipes must be kept clean, not bent below minimum radii (annex D), ends capped when idle, and reamed weekly with a tool 0.025 mm smaller than nominal bore to prevent throttling. Overall pipe length must not be reduced by more than 5 mm in service.
• Validation and documentation: A Statement of ISO test conditions (annex E) documents facility identity, test parameters and authorized signature. Equipment verification intervals and personnel authorization are defined.
• Special cases: If peak injection pressure exceeds 625 bar, bench capacity must be downrated per annex A.

Applications and users

ISO 4008-3 is used by:

• Automotive and diesel engine manufacturers for pump type‑approval or setting procedures
• Workshop technicians and calibration labs performing ISO benchmark tests
• Test bench manufacturers and service centers to ensure compliance with ISO test conditions
• Quality assurance and R&D teams validating pump performance, delivery and durability

Practical benefits include consistent test repeatability, interoperable test documentation, and clear acceptance criteria for pump delivery and peak pressure.

Related standards

• ISO 4008-1, ISO 4008-2 (other parts of fuel injection pump testing)
• ISO 4113 (calibration fluid)
• ISO 4093 (high‑pressure pipes)
• ISO 4010, ISO 7440 series, ISO 7446, ISO 4020, ISO 8984 (referenced test and component standards)

Keywords: ISO 4008-3, fuel injection pump testing, road vehicles, injection pump test procedures, calibration fluid ISO 4113, high-pressure pipes ISO 4093, workshop test schedules.