Condensation inside oil filler cap

[radek at istar.ca]

Hello group.
For some time I have been noticing condensation (little droplets of water) on the inside
of the oil filler cap of my 5-cyl Eurovan.  Coolant level has been
dropping very very slowly over the past few months, I had to add no more than 1/4 litre.
About ten months ago the timing belt and water pump were
changed by the dealer.  Immediately I noticed that when the engine was warming up, about
just as the temp nedle starts moving up, a grinding noise
appeared and then went away, more pronounced when it was cold outside.  Could there be any
link between the two?
Any suggestions where to look first?  Coolant leaking into the oil does not look like a
good proposition. TIA.
Radek.

'88 90Q
'93 Eurovan


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