Motor backs down when reaching 4300 rpm to 3000 rpm

[dcwshl]

Mercury 2002 50 hp four stroke runs ok until it reaches 4300 rpm, when trying to go full throttle at 4300 rpm motor backs down to 3000 rpm. Don't know what could be causing this?

 

[verado7]

Re: Motor backs down when reaching 4300 rpm to 3000 rpm

coulld be a faulty rev limiter

 

[nova23zz502]

Re: Motor backs down when reaching 4300 rpm to 3000 rpm

Had similar problem on a 115 4 stroke fuel injected. Remove the VST tank and clean out crap blocking off High Pressure pump (if so equiped.) Also make sure you have a 10 micron fuel filter in line before motors fuel system. Please let me know how you make out

 

[Jeep Man]

Re: Motor backs down when reaching 4300 rpm to 3000 rpm

'02 era fuel pumps had a problem with shaft binding at mid throttle after years of service. Later year pumps had the problem corrected. Low RPM and WOT works normally.