Clio's old HG was well gone, blowing coolant out the header tank. Put in a new gasket, new bolts etc, new belts- on starting runs well - no probs - no bubbling etc, but exhaust looked steamier than normal - did improve a bit after running for a bit, let some steam out the oil filler cap (presume mayonaise still lurking around the engine & sump etc)

Is this normal after a HG change or have I messed up with something?