Rotax 912 i series Operator's Manual page 68

7.1) Cooling system of the engine
General note
Cooling
Coolant
Expansion tank
Coolant tempera-
ture measuring
Effectivity: 912 i Series
OM Edition 1/Rev. 0
See Fig. 1.
The cooling system of the engine is designed for liquid cooling of
the cylinder heads and ram-air cooling of the cylinders. The coo-
ling system of the cylinder heads is a closed circuit with an expan-
sion tank.
The coolant flow is forced by a water pump, driven from the cams-
haft, from the radiator to the cylinder heads. From the top of the
cylinder heads the coolant passes on to the expansion tank (1).
Since the standard location of the radiator (2) is below engine le-
vel, the expansion tank located on top of the engine allows for
coolant expansion.
The expansion tank is closed by a pressure cap (3) (with excess
pressure valve and return valve). At temperature rise of the
coolant the excess pressure valve opens and the coolant will flow
via a hose at atmospheric pressure to the transparent overflow
bottle (4). When cooling down, the coolant will be sucked back into
the cooling circuit.
NOTE: The temperatur sensor at delivery is located in
cylinder head 4.
BRP-Powertrain
page 7-2
January 01/2012