The Mercury Marine serial number 1B507810 is 2 Stroke DFI (OptiMax) 250 PRO XS (3.0L DFI) engine that’s part of the outboard model 1250P83HD. It was produced in 2006. The engine displacement is 185.76, and the horsepower is 250DFI. The engine belongs to the serial range and catalog [1B426561 THRU 1B752546] – USA – Cat.# 90-898101403. Related components are listed below.