1978 Evinrude 85hp Model # 8589C Serial # J0005480Just bought this used boat. Motor history unknown but the power packs and ignition coils look fairly new. Spark plugs are in excellent condition. Rebuilt carbs and replaced fuel pump. Hooked Timing light to #1 spark plug and timing is 180 degrees out. I am a newby at outboard motors so is this normal?Motor will not start. It will back fire when the choke is ON. All wiring looks normal and in accordance with the manual. Can wires be swapped around somewhere to get the timing back t o normal.