engine has trouble at high rpms 1977 johnson 115

[glastronhp154]

i have a 1977 Johnson 115 that i recently had an ignition problem it would run fine for 15-20 minutes then it would not get up past 1500 rpms with out bogging or dying eventualy with the help of people on here i solved that problem with a new stator. now the boat will hole shot right up to cruising speed around 3500 and will try to open up but starts a high speed sounding sputter/almost sounds like its reving out but its not. it will very rarely go past 4000 rpms sometimes it will tho which is wierd and it will run up to 4600. the carbs have been cleaned 3 times now the coils have been replaced, the stator is new the plugs and wires are new , the fuel lines have been cleaned or replaced, the gas tank is new and fresh gas and seafoam are a standard for me. what do you guys think it could be drivvving meee nuuutss

 

[racerone]

Compression is ??

 

[emdsapmgr]

You said you cleaned the carbs. Did that include pulling out the high speed jets and visually inspecting them for debris/restrictions? How old is the fuel pump? When you were running at full throttle, does it help to constantly prime the fuel hose bulb?

 

[glastronhp154]

compression is 95 to 105 on all cylinders.carb is clean and yes visualy inspected but i will break them down again tommorw for the hell of it. havent tried pumping the bulb at high speeds keep in mind this boat is scary fast even at only 4000 rpms could i try choking at high speeds? the bulb seems to stay hard have never seen or felt it go soft. could it still be ignition related since the stator was a prblem maybe i need a new regulator the timer base looks brand new? no idea how old the fuel pump is but i inspected it and it seemed very new but im not familiar with these at all.

 

[glastronhp154]

pulled thhe spark plugs and cylinders 2 and 4 were wet and much cleaner than 1 and 3.

 

[glastronhp154]

on cylinder 3 it was yellowed