My cage has been leaking oil to the tune of about a litre a month. I've been told that it was a valve cover leak and it needs to be replaced (I assume the mechanic meant the gasket). We never got into pricing, so I want to know how much something like this would cost, parts and labour. Also, is this type of repair a typical repair an atypical repair on cars?
If it wasn't the gasket, what parts of the valve cover could cause a leak?