Normal Operation Checks
- During normal running, regular checks have to be made and precautions are to be taken
- Regular checks of the system and engine pressures and temperatures
- The values read off the instruments compared with those given in the commissioning records, taking into account engine speed and/or engine power, provide an excellent datum for estimating the engine performance. Compare temperatures by feeling the pipes. The essential readings are the load indicator position, turbocharger speed, charge air pressure, and exhaust gas temperature before the turbine. A valuable criterion is also the daily fuel consumption, considering the lower calorific value
- Check and compare between cylinders the mean indicated pressure, compression pressure, and maximum combustion pressures
- Check the operation of the oil mist detector
- Check all of the shut-off valves in the cooling and lubricating systems for the correct position. The valves for the cooling inlets and outlets on each engine must always be fully open in service. They serve only to cut off individual cylinders from the cooling water circuit during overhauls
- When abnormally high or low temperatures are detected at a water outlet, the temperature must be brought to the prescribed normal value very gradually. Abrupt temperature changes can cause damage
- The maximum permissible exhaust gas temperature at the turbocharger inlet must not be exceeded
- Check the combustion by observing the color of the exhaust gases
- Maintain the correct charge air temperature after the air cooler with the normal water flow. In general, higher charge air temperatures will result in less oxygen in the cylinder, which in turn will result in higher fuel consumption and higher exhaust gas temperatures
- Check the charge air pressure drop across the air filters and air coolers. Excessive resistance will lead to a lack of air in the engines
- The fuel oil has to be carefully filtered before being used. Open the drain cocks of all fuel tanks and fuel oil filters regularly for a short period to drain off any water or sludge which may have collected there. Maintain the correct fuel oil pressure at the inlet to the fuel injection pumps. Adjust the pressure at the injection pump supply manifold with the pressure-regulating valve in the fuel oil return pipe, so that the fuel oil circulates within the system at the normal delivery capacity of the fuel oil circulating pump
- The heavy fuel oil has to be sufficiently heated to ensure that its viscosity before the inlet to the fuel injection pumps lies within the specified limits
- Determine the cylinder lubricating oil consumption. Extended service experience will determine the optimum cylinder lubricating oil consumption
- The cooling freshwater pumps should be run at their normal operating point, ie, the actual delivery head corresponds with the designed value. If the pressure difference between the inlet and outlet exceeds the desired value, the pump overhaul should be considered
- The vents at the uppermost points of the cooling water spaces must be kept closed
- Check the level in all water and oil tanks as well as all the drainage tanks of the leakage piping. Investigate any abnormal changes
- Observe the condition of the cooling freshwater. Check for oil contamination
- Check the charge air receiver drain manifold’s sight glass to see if any water is draining away and if so, how much
- Check the scavenge space test cocks to see if any liquid is flowing out with the charge air
- Check the pressure drop across the oil filters. Clean them if necessary
- The temperature of the running gear should be checked where possible by listening and observing the crankcase externally and monitoring the oil mist detector readings. Bearings that have been overhauled or replaced must be given special attention for some time after being put into normal service
- Listening to the noise of the engine will reveal any irregularities
- The power being developed by the cylinders should be checked regularly and adjustments made via the control system to preserve cylinder power balance
- Centrifuge the lubricating oil. Lube oil samples should be taken at frequent intervals and sent ashore for analysis
- Check the exhaust valves are rotating and operating smoothly. If not, the valve not rotating normally has to be overhauled at the next opportunity
