I have a 115 hp otpi max pro sx 2 stroke that I purchased last year serial number 2B121769. What should the water pressure be for this motor? It's seem low to me it anywhere from 6 to 7 lbs at idle to 11 to 12 at 5000 rpm. I have a smart craft gauge. I know there are a lot of 115 hp out there on tins. Thanks for any info on this