Maybe when the timing belt was put on it was not put on right and now the valve timing is off. I just did a head gasket on a 96 Zetec. Had overheating problems and was exhaust gas getting into the coolant. One or more of the plugs was getting fouled though. With old plugs would not start and did same thing as yours. When new plugs were put in ran even with the blown head gasket. With new gasket runs fine and no overheating. We were very carefull to make sure the engine was in TDC when we took it apart and made sure we used a valve time tool when we put it back together. Also when you change the water pump on a 96 you have to take off the timing belt. So even for a water pump change you have to make sure the car is in TDC.
Rich S
