115 EFI four stroke fuel pump problems ???

have problem with 2008 115 efi four stroke at wot.(6300 rpm) starts intermitent miss, can back off to 5500 rpm and run all day without a miss. go back up to 5600/5700 and higher starts to miss again. seems to start the miss after eng. warms up. it had a ss 13.5x17 prop. when i got it. top rpm. was around 5300 rpm. changed to a 4 blade 13.25x15 alum. now tops out at 6300 rpm at about 40 mph. gps. pushing a columbia 18 ft. alum. am leaning towards fuel pump prob. i understand pressure should be about 42lbs. is there any high / low in that pressure? any other thoughts??? thanks in advance for any info. Lee p.s. changed out plugs /high/ low fuel filters. gives 6 beep alarm but no error codes

Re: 115 EFI four stroke fuel pump problems ???

You are hitting the rev limiter on this motor. Prop it so it does not turn above 5600 RPM. Motor is running as designed.

Re: 115 EFI four stroke fuel pump problems ???

thanks for the reply SXMERC.I was under the impression that factory prefered wot rpm for the 2008 115 efi was 5400 to 6800. thats why i replaced the s.s. 17 3 blade prop. with this 4 blade 15 prop to get the higher rpm. guess i will just back off for now. thanks again///checked my merc repair manual again. it states that a 2007/2011 115 EFT 1732 cc eng. w.o.t. should be 5800 /6400 the 115 efi 1741 cc is 5000/6000 mine is 1732. could still use some help please