Could there be a slightly different scenario, such as the water pump  locking
up causing the belt to break and the coolant loss being a symptom of a
failed water pump? Was the pump making any appreciable noise prior to the belt
breaking/coolant loss? How was the engine temperature? Any higher than normal?
After the incident did the pump spin freely without any unusual noises  or
resistance? I'm just thinking along the lines of the typical water  pump short
life span in our vehicles and how the symptoms that you describe  could possibly
follow a water pump failure.

David Clarkson
90 Westy (253k and on the 5th  water pump)

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