Engine worries.

[Adamsindrey]

The car is a 93-94 L reg carina E, 4 cylinder 2 litre petrol.
140 000 miles, 50,000 miles maybe more on the same plugs, air filter and the same oil filter (oil filter was replaced bout 5,000 miles ago).
and about 90,000 miles on the same cam belt (replaced at 60,000ish and that was within the first year of use (ex rep car)).
it has a steady oil leak which we top up every 2 weeks (roughly 60 miles a week useage) as it sinks from the top of the full level on the dip stick down to half way.
the oil drips off the differential (front wheel drive) and untill now i didnt really know why. the engine on the car is angled slightly backwards and with some more investagation, it seems to be the oil is seepin out the bak of the head gasket dripping down the back of the engine and off the differential.
another reason i think this is that occasionally the inside of the oil filler cap has white creamy stuff on it. this is to do with oil and water mixing isnt it??? and thats because the head gaskets leaking isnt it?
the car never gets off the cold mark on the guage untill u do lots of motor way miles then stop in traffic for about 5 minutes. but even then its less than half way up the guage.
Should I (its my dads car but im chief mechanic :b ) be worried about the cam belt going and screwin the head or the gasket going and needing to find another engine?

P.S the engine doesn't get thrashed, never above 3500rpm!

Thanx Adam

[Greenblurr93]

just change the head gasket, it seems like u know where its coming from.

[Adamsindrey]

and the cam belt?

[Greenblurr93]

its always good to change belts while you have them off, its just easier. But if the belt is still in god condition (no cracks or chips) Then u dont NEED to.