309 crankcase pressure

[robthespaniard]

I have just aquired a 309 1.4 petrol . It has an oil escape which comes up through the dipstick..... I am assuming that it has a buildup of pressure in the crankcase. Is there a breather that could be blocked or am I looking at an internal problem. The engine is not smokey and doesnt seem to spew loads of oil either from the exaust or the dipstick ... any clues ???