krypto 1 in CT

just running around 4000 rpms only around 5 hrs on rebuild it and it sounded strange let off and its knocking like a bi,,h all the gauges were reading fine.not sure what to do.i dont want to loose the season maybe buy a hp 500 long block.does merc sell replacement hp 500 (carb) longblocks outright? .i guess thats what you get when you buy a used boat with the motor out getting dynoed by the owners engine guy and get no build sheet.i new it wouldnt last the oil pressure was only like 10lbs at idle warm with a mech gauge and merc 25/40 oil to much bearing clearnce ill bet.anybody know where i could get a hp 500 long block from quickly?

Pure Energy

www.1800runsnew.com They don't have a "500hp" replacement but do have some good motors. They are in Mass. and it took 1 day for me to get mine in NJ.

P.S. I Procharged mine and they run great.