Ford WSS-M98P14 Flex and Plastic Materials Used in Biodiesel Fuels

The “Ford WSS-M98P14 Plastics used in Flex and biodiesel fuels” standard, developed by Ford Motor Company (Ford), describes the minimum requirements for fuel system and urea components. This standard consists of the following sections:

• WSS-M98P14-A1 Performance of plastic fuel tube materials used in flexible fuels.
• Performance of elastomeric fuel hose materials used in WSS-M98P14-A2 Flex fuels.
• WSS-M98P14-A3 Performance of plastic fuel tube materials used in flexible fuels.
• WSS-M98P14-A4 Performance of elastomeric materials used in Flex fuels.
• WSS-M98P14-A5 Performance of plastic fuel tube materials used in biodiesel fuels.
• WSS-M98P14-A6 Performance of elastomeric fuel hose materials used in biodiesel fuels.
• WSS-M98P14-A7 Performance of plastic materials used in biodiesel fuels
• WSS-M98P14-A8 Performance of elastomeric materials used in biodiesel fuels.
• Performance of WSS-M98P14-A9 Urea SCR Materials
• WSS-M98P14-A10 Performance of plastic fuel pipe materials used in CNG fuels.

This standard was initially published for materials used in fuel, urea selective catalyst reduction (SCR) systems, and compressed natural gas (CNG). This specification covers elastomeric and plastic materials. Fuel exposure includes flexible fuels (for gasoline and alcohol-fueled vehicles) and biodiesel fuels (for mineral and bio-derived diesel fuel vehicles).

Unless otherwise specified by Ford Materials Engineering, the required tests are listed in this standard appendix (Appendix A).

This standard requires the use of approved welds. When listed in a drawing, CAD file, or other document, only welds specified in the Ford approved weld list may be used. Test results must be approved by product engineering. If deemed acceptable, materials engineering will add the materials to the approved weld list.

In the ever-evolving world of automotive engineering, Ford Motor Company has long been at the forefront of innovation, particularly in adapting vehicles to alternative and sustainable fuel sources. A key element supporting this progress is the Ford WSS-M98P14 standard. This standard sets stringent performance criteria for materials used in fuel systems. Designed to guarantee durability, safety, and compatibility with emerging fuels such as flexible fuels, biodiesel, and even compressed natural gas (CNG), these standards are critical for suppliers and engineers working on the next generation of Ford vehicles. As global regulations encourage the reduction of carbon emissions and the increase of fuel flexibility, the Ford WSS-M98P14 and similar standards help bridge the gap between traditional petroleum-based systems and environmentally friendly alternatives.

The Ford WSS-M98P14 series of standards emerged in the early 2000s with the increasing demand for vehicles that could run on ethanol-based flexible fuels (E85, a blend of up to 85 percent ethanol and gasoline) and biodiesel (blends containing up to 20 percent biodiesel, such as B20). Traditional fuel system components such as hoses, pipes, and gaskets were prone to degradation when exposed to these aggressive biofuels, leading to problems such as swelling, cracking, or permeability that could compromise vehicle performance and safety. To address this issue, the Ford WSS-M98P14 standard was developed.

This standard is always used in conjunction with the Ford WSS-M99P1111-A standard, a complementary specification that defines the essential requirements for fuel system and urea (for selective catalytic reduction in diesel engines) components. The continuously updated Ford WSS-M98P14 standard ensures that elastomers (rubber-like materials) and plastics can withstand the chemical and thermal stresses of modern fuels without premature degradation.

The Ford WSS-M98P14 standard family is not a single standard, but a package of interconnected standards, each focusing on a specific material-fuel interaction. According to Ford's official engineering documents, a breakdown of the basic variants is as follows:

• WSS-M98P14-A1: Defines the tensile strength, permeability resistance, and burst pressure for plastic pipes exposed to E85 mixtures. Primary applications include fuel lines in flexible fuel vehicles.
• WSS-M98P14-A2: Focuses on testing rubber hoses for volume expansion, stiffness variations, and leakage rates. Primary applications include high-pressure hoses in ethanol-compatible engines.
• WSS-M98P14-A4: Focuses on broader elastomer testing for seals and O-rings. Primary applications are engine components in E85 compliant powertrains.
• WSS-M98P14-A5: Focuses on oxidation and hydrolysis resistance in B20/B100 blends. Primary applications focus on diesel fuel systems.
• WSS-M98P14-A6: Focuses on ester-based degradation resistance in hoses. Primary applications are biodiesel distribution lines for commercial fleets.
• WSS-M98P14-A7: Focuses on general plastic compatibility, including post-exposure impact resistance. Key applications include tanks and reservoirs in diesel hybrids.
• WSS-M98P14-A8: Focuses on long-term aging tests for out-of-hose elastomers. Primary applications are seals in biodiesel injection systems.
• WSS-M98P14-A10: Focuses on permeability and fatigue resistance for natural gas at high pressures. Key applications are CNG-adapted vehicles in developing markets.

These variants are extensively cross-referenced to create a comprehensive testing ecosystem, for example, built upon A1, A3 (plastics in flexible fuels), and A5. Suppliers are required to certify materials through Ford's laboratory protocols, which typically involve accelerated aging in fuel-soaked environments at high temperatures (e.g., 60 degrees for 168 hours).

The Ford WSS-M98P14 standard essentially uses a versatile testing system to simulate real-world abuses. Metrics for elastomers include:

• Volume change: After immersion in the test fuel, it should not exceed 30 percent, which prevents the hose from swelling.
• Tensile strength protection: Must be at least 70 percent after exposure, which ensures the hoses do not break under pressure.
• Permeability limits: Fuel vapor leakage for plastics remains below 15 g/m2/day, reducing emissions.

Plastics undergo similar scrutiny and also undergo burst tests up to four times the working pressure. Biodiesel varieties add microbial growth and oxidative stability controls, as biodiesel fatty acid methyl esters (FAMEs) can accelerate material degradation.

These are not arbitrary thresholds; they are derived from fleet data and fault analysis.

For both engineers and enthusiasts, understanding the Ford WSS-M98P14 standard is a masterclass in materials science.

For many years, our organization, with its competent and experienced staff, has been understanding the needs of its customers, providing the advanced testing services they require, and assisting them in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services to businesses in accordance with the "Ford WSS-M98P14 Flex and plastic materials used in biodiesel fuels" standard.