Trains had begun operating again around 3.15pm Wednesday, but passengers were still experiencing delays after a freight train with mechanical problems at Warnervale had caused all trains on the Newcastle and Central Coast lines, running between Wyong and Morisset to earlier in the afternoon.
A Transport Management Centre spokesperson said replacement buses were being organised, but had yet to arrive on site at around 3pm Wednesday.
Passengers have been advised to delay their trip or allow plenty of extra travel time.
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