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 indicate potential gauge or engine problems. Problems may also be indicated by gauge readings that change even if the readings are within specifications. Determine the cause of any significant change in the readings. Then, correct any cause of any significant change in the readings. Consult your Caterpillar dealer for assistance.
Caterpillar requires one lamp in addition to the gauge package that is normally provided. The "DIAGNOSTIC" lamp is yellow or amber. The "DIAGNOSTIC" lamp will communicate the status of the engine's electronic system and the status of the Diesel Particulate Filter (DPF). The optional red "WARNING" lamp is also available. The red "WARNING" lamp warns the operator of engine problems.
The following conditions are some examples of the engine problems:
- Low oil pressure
- High coolant temperature
- Low coolant level
- High inlet air temperature
- High exhaust back pressure
| Engine Oil Pressure - Typical oil pressure for an engine at rated speed with SAE 10W30 or with SAE 15W40 is 240 to 480 kPa (35 to 70 psi). |
A lower oil pressure is normal at low idle. If the load is stable and the gauge reading changes, perform the following procedure:
- Remove the load.
- Reduce engine speed to low idle.
- Check the oil level. Maintain the oil level at the proper amount.
The "DIAGNOSTIC" lamp will turn on if the oil pressure drops below 35 kPa (5 psi) at low idle rpm. The diagnostic code will be logged in the Engine Control Module (ECM).
| Engine Oil Temperature - This gauge indicates the engine oil temperature. An oil temperature that is higher than normal indicates a heat problem in the lubrication system and/or the cooling system. This problem can damage the cylinder heads, the cylinder liners, the pistons, and the crankshaft bearings. |
| Jacket Water Coolant Temperature - Typical temperature range is 88 to 102 °C (190 to 215 °F). The maximum allowable temperature with the pressurized cooling system is 105 °C (220 °F). Higher temperatures may occur under certain conditions. The water temperature reading may vary according to load. The reading should never exceed the boiling point for the pressurized system that is being used. |
If the engine is operating above the normal range and steam becomes apparent, perform the following procedure:
- Reduce the load and the engine rpm.
- Inspect the cooling system for leaks.
- Determine if the engine must be shut down immediately or if the engine can be cooled by reducing the load.
| Tachometer - This gauge indicates engine speed. When the throttle control lever is moved to the full throttle position without load, the engine is running at high idle. The engine is running at the full load rpm when the throttle control lever is at the full throttle position with maximum rated load. |
Note: The high idle rpm and the full load rpm are stamped on the Information Plate.
| Ammeter - This gauge indicates the amount of charge in the battery charging circuit, or the amount of discharge in the battery charging circuit. Operation of the indicator should be to the right side of "0"(zero). |
| Service Hour Meter - This gauge indicates the total operating hours of the engine. Hours of operation are logged in the ECM. A service tool is needed to retrieve the hours from the ECM. A Service Hour Meter may be installed on the engine. |
| Fuel Pressure - This gauge indicates fuel pressure to the electronic unit injectors from the fuel filter. The indicator should indicate the "NORMAL" range. A decrease in fuel pressure usually indicates a plugged fuel filter. |
| Fuel Level - This gauge indicates the level of fuel in the fuel tank. The fuel level gauge registers the fuel level only when the ignition switch is in the ON position. |