Fuel Systems, Hydraulics, and Preventive Maintenance
Fuel systems, PTO, hydraulics, pre-trip inspection, DVIR, ELD, and advanced air brake diagnostics.
- Describe fuel system maintenance and fuel quality requirements
- Explain PTO and hydraulic system operation and maintenance
- Perform pre-trip inspection and complete a DVIR
- Explain ELD requirements and advanced air brake diagnostic procedures
Lesson 1
Fuel Systems and Fuel Quality
Fuel System Maintenance
Diesel fuel systems require clean, water-free fuel to operate reliably. Water in diesel fuel causes injector corrosion, microbial growth, and reduced lubricity. Fuel filters must be changed at specified intervals, and water separators must be drained regularly.
Fuel contamination causes the majority of common rail injection system failures. Particles as small as 4 microns can damage high-pressure pump and injector components. Multi-stage filtration with primary (coarser) and secondary (finer) filters protects the system.
Cold Weather Fuel Issues
Diesel fuel gels in cold weather when paraffin wax crystals form and plug filters. The cloud point is the temperature at which wax crystals first appear. The pour point is the temperature at which fuel will no longer flow. Winter blended fuels and anti-gel additives help prevent cold weather fuel problems.
Fuel Gelling Prevention
Use winter-blend diesel fuel, install fuel heaters, and keep fuel tanks as full as possible to minimize moisture condensation. Never mix gasoline with diesel to prevent gelling - it damages injection components and reduces lubricity.
Fuel contamination is the leading cause of common rail injection failures. Multi-stage filtration, regular water separator draining, and proper fuel quality management are essential. Diesel fuel gels in cold weather at the cloud point temperature.