Engine Stall 1500 RPM, and over 4800 RPM

[jeltman]

After two hours of operation, my OX66 250HP will occasionally stall at 1500-1900 RPM, sputters then stalls. Will immediatly restart. Also when accelerating quickly (over 5000 RPM) it will run for 5 seconds and then quit. All fuel filters changed, high pressure pump registers 32PSI, after slowly building up from zero. Does this sound like a Hi pressure, or low pressure pump issue? Or something else?

[boats.net]

Would have to check fuel pressure at the time it stalls or quits to tell if a fuel pump problem.