Rocam engine water bottle pressurized
I have a 2006 Bantam rocam engine
that overheats and the water bottle
gets pressurized. Oil and water don't
mix. Engine runs fine other than the
overheating problem. What could be
It could be the head gasket, test it with Block Tester, it will tell you if the pressure is being caused by hydrocarbon combustion gases. (BTW not all blown head gaskets result in cross contamination of water/coolant.)
Check also the operation of the thermostat.