Can this cold cause mayo on the cap?

[julian]

Hi,

Was just driving and a heard a weird 'thump' noise from the engine.

The head gasket, water pump etc. were changed a month ago so I checked the cap and there was mayo on it and also a bit visible under where the cap sits. Can this have been caused by the cold? The journey was 15 miles. Or has the gasket gone again? It hadn't cleared up after the return journey.

Or, the washer water had frozen so could the noise have been some ice or tube giving way maybe?

Any opinions?

Julian.

[polo-sib]

Unless your coolant is decreasing I doubt it, the mayo is a common product made when the engine oil is breaking down, which is caused by short journeys or from the oil not being changed for a long period.

[julian]

Thank you. The oil does need changing, can you believe the garage never did it with the head gasket even though I told them there was enough spare in a bottle in the boot!!

Cheers.