An alarm for the maximum exhaust temperature in each cylinder is beneficial because it can provide an early indication of localized problems specific to an individual cylinder. Common causes include:

• Blocked or sticking fuel injector.
• Dripping injector nozzle causing afterburning.
• Leaking exhaust valve due to a damaged seat or valve.
• Incorrect fuel timing or shifted fuel cam.
• Stuck fuel pump rack.
• Low compression caused by worn liners or piston rings.

This system allows for targeted troubleshooting and preventive maintenance, potentially avoiding major breakdowns. However, it does not account for situations where cylinders operate with a significant temperature imbalance, which can still cause damage.

This enhances (a) by adding minimum temperature alarms. Deviations from the normal operating temperature range (both high and low) indicate potential problems. A minimum temperature could suggest no fuel injection, a broken exhaust valve, or advanced fuel timing, all potentially leading to engine imbalance, component overloading, and eventual damage. The combined system offers more comprehensive monitoring, detecting a wider range of issues than maximum temperature monitoring alone.

This approach combines the benefits of (a) with a system detecting power imbalances. While some temperature variation between cylinders is normal, a significant difference (e.g., >35°C) indicates a problem. This is because an uneven distribution of power creates high stresses on the crankshaft, potentially leading to engine damage. The alarm system provides early warning of power imbalances that might not be immediately apparent from individual cylinder maximum temperature monitoring alone.

Each cylinder is fitted with an exhaust gas temperature sensor (thermocouple). These sensors send temperature readings to a central control unit (CCU). The CCU compares each reading against the maximum allowable temperature; if any exceed the set point, an alarm is triggered. Simultaneously, the CCU calculates the average exhaust temperature of all cylinders. It then compares each individual cylinder temperature against this average. If the difference between any cylinder’s temperature and the average exceeds 35°C, another alarm is triggered, indicating a significant power imbalance.