Have the water pump replaced promptly. Coolant from the weep hole behind the timing belt indicates a failing water pump, and continued leakage can soak and damage the timing belt.
The owner of a 1990 Mazda 626 reports coolant leaking from what looks like a weep hole on the front engine cover behind the timing belt. A user suggested plumber's tape on a hose. A Mazda technician advised having the water pump replaced quickly because a failing pump can soak the timing belt with coolant and cause it to fail.
