Bought a boat with what the owner said was an Evinrude 225hp. He didn't know the year, etc...there is no tag or label of any kind on the motor, not even an Evinrude or 225hp logo on the cowl. I've kind of pinned it down to a 1988 and recently ordered thermostats for a 1988 that were the exact ones that I took out of the motor. So I know I'm closing in anyway. There is a welch plug about the size of a quarter on the rear of the powerhead above the V6 marking. Was told this would be the model number but I can't find any info on it at all. The number is G253240 and if anyone can help with this or send me in the right direction it would be much appreciated, thanks.