Hi Kerry, if you are only doing short journeys the salad cream junge could be from condensation in the engine mixing with the oil as the engine is not getting hot enough too evapourate the condensation, the only way to find out for certain is to either have the compression tested or get a garage to do a "sniff test" on the expansion bottle, if the gasket has failed the fluid will turn fom blue to yellow
nigel, March 2009