LO 6-10 Identify and describe clean care practices

LO 6-10: Identify and describe clean care practices.

Clean Care Service Practices

Diesel engines and fuel systems are highly sensitive to contaminants such as dirt and water. While engines have always been adversely affected by wear factors caused by contaminants, smaller operating clearances, higher injection system pressures, and use of electrohydraulic components (the result of advances in technology) cause even the smallest amount of contaminants to be more destructive in today’s engines Figure 41. Large heavy-equipment shops operating underground were the first to discover the benefits of what are commonly called clean care practices. This means that before servicing any engine or fuel system components, such as injectors, fuel lines, high-pressure fuel pumps, and so on, it is critical that no contaminants enter the fuel system or internal engine component Figure 42. By implementing shop practices to eliminate contamination of fluids, such as fuel and lubricating oils and internal engine components, the amount of money saved is many times more than the investment costs needed to establish clean care practices. Clean care shop practices extend the service life of replacement parts and major components and also reduce maintenance costs through longer component service life and increased equipment productivity or uptime. From a business perspective, clean care practices have the added benefit of increasing resale value and return on investment (ROI), lowering overall lifetime costs of operation, and increasing productivity; the vehicle will provide more efficient service with improved reliability Figure 43.

FIGURE 06-41: The operating clearances and pressures of fuel system parts make them more sensitive to premature wear caused by contaminants.

FIGURE 06-42: It is critical that during service, all high-pressure injection lines and fittings are capped to prevent entry of contaminants. Do not remove caps until it is necessary to reconnect fittings and lines.

FIGURE 06-43: The relationship between preventive maintenance costs and resale price.

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