3016 hst No start after installing new battery

[Tominblaine]

Hello all I'm new here and a newbie to tractors, I replaced the battery today and now it won't start, glow plug indicator works, it cranks, white smoke from exhaust but she won't fire up, what did I miss, also cleaned batt connectors. additional info, I just started it with the old battery in it just minutes before and let it run for about 15 minutes.

Thanks in advance for your replies/help