1997 ford 250 diesel
Alternate went out so changed it. But now truck wont start,
it turns over it wants to start and it's trying to start. It's got
fuel and fully charged batteries... can't figure it out.
You could have some bad glow plugs. If other drivers or you don't allow them to finish heating up the cylinder every time you start it, the glow plugs can blow out over time. Sometimes it only takes one time to blow them. It may start on a real warm day with bad glow plugs but never on a cold day. If you have a block heater installed it may start with an overnite warming. If so, most definitely bad glow plugs.