3618 Engine Caterpillar

Note: The following symbols are used for installation with the Marine Monitoring System (MMS) only.

Gauges provide indications of engine performance. Ensure that the gauges are in good working order. Determine the normal operating range by observing the gauges over a period of time.

Noticeable changes in gauge readings can indicate potential gauge or engine problems. Problems may also be indicated by gauge readings that change even if the readings are within specifications. Determine and correct the cause of any significant change in the readings. Consult your Caterpillar dealer for assistance.

Your engine may not have the same gauges or all of the gauges that are described. For more information about the gauge package, refer to the literature that is provided by the OEM of the vessel.

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NOTICE
If no oil pressure is indicated, STOP the engine. The engine will be damaged from operating without oil pressure.

Engine Oil Pressure - This gauge indicates the pressure of the engine oil. The pressure will be highest after a cold engine is started. The pressure will decrease as the engine warms up. The pressure will increase when the engine rpm is increased. The pressure will stabilize when the engine rpm is stable. The typical pressure at low idle rpm is 172 kPa (25 psi). The typical pressure above 650 rpm is 448 kPa (65 psi).

Oil Filter Differential Pressure - This gauge indicates the difference in pressure between the inlet side and the outlet side of the engine oil filters. As the oil filter elements become plugged, the pressure will increase. Replace the engine oil filter elements when the oil filter differential pressure reaches 103 kPa (15 psi).

Engine Oil Temperature - This gauge indicates the engine oil temperature after the oil has passed through the oil cooler. The oil cooler is thermostatically controlled. The oil temperature is controlled by an 70 °C (158 °F) temperature regulator that is in contact with the oil. The pump for the aftercooler and the oil cooler pumps coolant for the engine oil.

Crankcase Pressure - This gauge indicates the pressure that is inside the crankcase. The typical pressure is 0.35 kPa (.051 psi). Changes in the pressure may indicate problems with the following components: crankcase breathers, pistons, piston rings and cylinder liners.

Aftercooler and Oil Cooler Water Temperature - This gauge indicates the temperature of the coolant at the inlet to the aftercooler and oil cooler circuit. The water temperature is regulated by water temperature regulators. If the cooling system cannot remove enough heat from the water, then the engine cannot be cooled properly. An oil temperature that exceeds the normal oil temperature may indicate that a problem has occurred in the lubrication system and/or the cooling system. Those problems may involve the following components: water temperature regulators, oil coolers, cylinder heads, cylinder liners, pistons and bearings.

Jacket Water Coolant Temperature - This gauge indicates the temperature of the engine coolant at the outlet for the jacket water. The temperature may vary according to the load. The temperature should never be allowed to exceed the boiling temperature of the pressurized cooling system. The jacket water coolant temperature is regulated to a temperature of 85 °C (185 °F) for the jacket water.

If the engine is operating above the normal temperature range, perform the following procedure:

1. Reduce the load and/or the engine rpm.

2. Inspect the cooling system for leaks.

3. Determine if the engine must be shut down immediately or if the engine can be cooled by reducing the load and/or the rpm.

Inlet Manifold Air Temperature - This gauge indicates the inlet manifold air temperature after the aftercooler. As the inlet air increases in temperature the following conditions occur: expansion of the air, less oxygen in the cylinders and less power. If the temperature of the inlet air is too high during full speed and load operation, the engine may consume excessive fuel. The typical inlet manifold air temperature is 40 to 50 °C (104 to 122 °F).

Inlet Manifold Air Pressure - This gauge indicates the air pressure (turbocharger boost pressure) in the air inlet manifold after the aftercooler. The pressure depends on the engine rating, the load, and the operating conditions. To establish the normal inlet manifold air pressure, compare the data from the gauge to the data from the engine commissioning and look for trends.

Air Restriction - This gauge indicates the difference in air pressure between the inlet side and the engine side of the air filter element. The air restriction is measured at the air inlet to the turbocharger. As the air filter element becomes plugged, the difference in pressure between the two sides of the air cleaner element will increase. The normal air restriction for the engine is 1.25 kPa (5 inches of H2O). Clean the air cleaner elements or replace the air cleaner elements when the air restriction reaches 2.5 kPa (10 inches of H2O). Maximum air restriction is 3.7 kPa (15 inches of H2O).

Turbocharger Exhaust Inlet Temperature - This gauge indicates the temperature of the exhaust gas at the inlet of the turbocharger. The normal operating temperature range is from 570 to 630 °C (1058 to 1166 °F). The maximum continuous temperature is 650 °C (1202 °F).

Exhaust Port Temperature - This gauge indicates the temperature of the exhaust gas from each individual cylinder. The temperature is measured at the exhaust port of each cylinder head. The exhaust temperature will vary slightly between the cylinders. Individual cylinder exhaust temperatures should not vary by more than 60 °C (140 °F) from the average of all of the cylinder exhaust temperatures.

Tachometer - This gauge indicates the engine rpm.

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NOTICE
To help prevent engine damage, never exceed the high idle rpm. An overspeed can result in serious damage to the engine. The engine can be operated at high idle without damage, but the engine should never be allowed to exceed the high idle rpm.

Note: The high idle rpm and the full load rpm are stamped on the Information Plate.

Engine Hours - This gauge indicates the duration of engine operation.

Fuel Pressure - This gauge indicates the fuel pressure to the engine from the fuel filter. The typical fuel pressure is 415 to 676 kPa (60 to 98 psi). The fuel pressure will decrease as the fuel filter differential pressure increases. A decrease in fuel pressure usually indicates a plugged fuel filter.

Fuel Filter Differential Pressure - This gauge indicates the difference in fuel pressure between the inlet side and the outlet side of the fuel filters. As the fuel filter elements become plugged, the difference in pressure between the two sides of the fuel filter increases. Replace the fuel filter elements when the fuel filter differential pressure reaches 69 kPa (10 psi).

Air Start Manifold Pressure - This gauge indicates the air pressure that is available for starting the engine. The standard air starting motor requires a minimum of 1034 kPa (150 psi).

Note: The following gauges are optional. These gauges may be mounted on a gauge panel or in a remote location.

For information about marine transmissions, refer to the literature that is provided by the OEM of the marine transmission or the vessel.

Marine Transmission Oil Temperature - This gauge indicates the temperature of the oil that is in the marine transmission. The measurement depends on the temperature of the water and the quantity of the water that is pumped through the marine transmission oil cooler.

Marine Transmission Oil Pressure - This gauge indicates the oil pressure in the marine transmission. The measurement depends on the temperature of the oil and the quantity of the oil that circulates through the marine transmission lubrication system.

Note: An optional gauge can be provided in order to indicate the oil pressure of the marine transmission or other driven equipment. For information about the driven equipment, refer to the literature that is provided by the OEM of the driven equipment or the vessel.