"Have pair 2003 BF225's and when I run for 15-39 minutes at 4000RPM plus an audible alarm sounds on the starboard engine and it drops down to 800 rpm. If I try to give gas it runs rough with no RPM increase. Turn the key and it will star back up and run great for anoth 15 - 30 min. No warning lights come on and the alarm is a continuous alarm.
Replaced O2 sensor, Racor fuel filters, low pressure fuel filters and cleaned water seperator.
What next?????
I am thinking high pressure fuel filter."