I've bought a C70 GS T 20V which has oil residue in the coolant header tank. However, there is no sign of water getting into the block and the oil cap is clean with no 'cheese' on it and the car runs perfectly with no over-heating problems at all.

The car does use a small amount of oil but it does have an oil leak somewhere on the sump which I was putting down to the use of oil, and we are talking small amounts of oil.

There is no residue of any type from the exhaust under any driving conditions and the car has only done 92k. I've now done 400 miles since getting it and it hasn't missed a beat and drives lovely.

I'm not sure whether to leave and see if anything changes significantly or, do the cylinder head gasket now as a pre-emptive!
Is the head gasket straightforward on these vehicles or do I need special tools etc?

Any suggestions or advice gratefully received as I'm new to Volvos!

 

You may have a leak in the heat exchanger at the back of the oil pan. Had a car that had copious amounts of oil in the cooling system. You have to try deduce how much oil and if it increases over time.