Which instrument helps determine when preventive maintenance is due by tracking runtime?

Which instrument helps determine when preventive maintenance is due by tracking runtime?

• A. Tachometer
• B. Oil pressure gauge
• C. Service hour counter
• D. Fuel gauge

Answer: (C)

Preventive maintenance is typically scheduled based on how long the machine has been operated, not just the calendar. The service hour counter records total hours of operation, so you can set and follow maintenance intervals (like every 100 or 250 hours). When the counter hits the scheduled interval, you perform the required service tasks, ensuring things like oil changes and filter replacements happen on time. The tachometer measures engine speed (RPM), which helps with safe operation but isn’t used to time maintenance. The oil pressure gauge shows lubrication status, not run-time. The fuel gauge only indicates how much fuel remains. So the service hour counter is the tool that ties maintenance timing to actual runtime.

Preventive maintenance is typically scheduled based on how long the machine has been operated, not just the calendar. The service hour counter records total hours of operation, so you can set and follow maintenance intervals (like every 100 or 250 hours). When the counter hits the scheduled interval, you perform the required service tasks, ensuring things like oil changes and filter replacements happen on time. The tachometer measures engine speed (RPM), which helps with safe operation but isn’t used to time maintenance. The oil pressure gauge shows lubrication status, not run-time. The fuel gauge only indicates how much fuel remains. So the service hour counter is the tool that ties maintenance timing to actual runtime.