- Industrial Engine:
- C9.3 (S/N: C9N1-UP)
- C13 (S/N: KWJ1-UP)
- C15 (S/N: LDN1-UP)
- C18 (S/N: BDN1-UP)
Some condensation may be noticed in the crankcase due to the addition of the NOx Reduction System (NRS). This moisture will typically collect on components such as the oil fill tube, the fill cap, and the oil level gauge. This collection is due to the components distances from the warmer parts of the engine. Some light rust on the inside of the oil fill tube may also be noticed as a result of the moisture buildup. The recirculated exhaust gas carries some water content which is a by-product of the combustion process. This results in some moisture entering the crankcase through blow-by gases. This situation occurs more frequently in conditions of extended low idle and light load operation due to the cooler engine oil and coolant temperatures.
No action is needed to correct this issue. Caterpillar has monitored this situation through thousands of hour of field testing. Once the engine coolant and oil temperatures reach normal operating temperatures, the moisture content will evaporate.
Note: The Caterpillar specified engine oils are formulated to operate effectively with some moisture content.