As you say,,,head gasket already done....he has saved the gasket to show me tomorrow,i have known this mechanic many years and trust him......although the day before i took the car to him it did produce white smoke from the exhaust...on the morning of taking the car to him on the 4/5 mile journey to the garage it was billowing out so much white smoke that i could not see the road behind me...the low level coolant light came on and i stopped the car and waited 30 minutes before filling the coolant bottle up..it struggled to restart but did and i manage to go the other mile to get to him,by which time the coolant had dropped below again...thus a lot of water entered the sump and exhaust which makes me think that he is correct....anyway i will let you know tomorrow once i have examined the gasket,,,,,and i will get some wynes and flush it tomorrow....thanks for the advice...