Expansion cap leak.

[dvhttn]

OK. Coolant leaking from the expansion tank cap - as evidenced by a) occasional 'STOP Engine' lights and topping up and b) 'spots' of coolant over the top of the expansion tank. As the cap was very easy to screw in/out, whereas previously it was very tight when nearly in fully, I got myself a new cap (from VW). But that's the same ...... now it does have a seal with it so that's OK, so has anyone had the tank neck, where the cap screws into, wear on them before? I see that there is a metal ring in the neck that does have wear marks on it but ......

Anyone? Otherwise it'll be a new tank from Carparts4less in the post ....

Ta.