COMCO IKARUS
Maintenance Manual C42 Series
MaintenanceManual C42-
Series_Issue_VII_18.02.2014.doc
Revison No.:1 26 from 107
2.5.4 Cooling system:
The cylinder heads of the Rotax 912UL engine are liquid-cooled whereas the cylinder
barrels are air-cooled.
In the case of the C42 / C42 UK, there are separate cooling systems for the coolant
and the oil.
In the case of the C42B / C42B UK/ C42E, only the coolant is cooled by a cooler. The
coolant and oil systems are connected to one heat exchanger, thus the temperatures
of both fluids adapt to each other. The temperatures of the coolant, oil and cylinder
head of the C42B / C42B UK / C42E are, therefore, almost identical. Due to heat
exchange the oil also warms up faster during the run-up phase. It is, however, still
necessary to mask the water cooler if optimum engine temperature (>90°C) is to be
achieved during cold weather operation (max. one third of the surface may be
covered with tape or self-adhesive neoprene).
More detailed information on engine cooling and the relevant maintenance measures
are to be found in the appropriate Rotax documents.
Figure 24: Cooler C42 / C42 UK
Figure 25: Cooler C42B / C42B UK /C42E
heat exchanger