1990 jonhson 50

[gabriel charest]

i have a big problem whit a 1990 jonhson 50 horsepower. The engine cut after 5000 rpm sound a rev limiters ,,this models have the powerpack under the flywheel,, the powerpack have the rev limiters inside .. i change the powerpack ,try ..have the same problem ,,change the triggers,change the coils and put a new powerpack,check jet in carb,,the carb is clean ,,change the plug ,check timing ,check gas ,,disconect heat sensor but i have still the same problem ''the problem sound whit fire but i change everything '' i cant just understand this engine its the very bad engine