Johnson 90 hp rough fast idel

Macca1500s

Seaman Apprentice
Joined
Jul 19, 2015
Messages
32
guys, thanks for looking, I'm seriously new to this outboard thing, and have a little question

i have a 1999 60 degree 90 hp Johnson "Ocean Pro"

as its still our winter/autumn here in Australia, i haven't been using this boat much.

just purchased in July.

so every few weeks i start it up and run it just to keep everything working.

today however i noticed that if i rev it in neutral, just using the linkage to the carby butterflies, at around 2500/3000 it seems to be missfiring

it seems that it looses a cylinder accompanied by a burst of smoke then goes on doing this ( i only hold it at that point for a few seconds.)

i thought what if i move the advance at the same time, it might be different , however the revs build so fast i decided not a good idea.

so while ensuring it was safe i stuck it in gear and revved it to 2500/3000 and again it seemed to have a random miss.

back at idle or a little faster all seems normal.

i didn't think to do it at the time but a couple of minutes later i checked the head temps with an IR gun , they were all within a couple of degrees of each other ( not very relevant i know)

what are your thoughts, am i worrying over nothing, maybe under load in water its ok!!

maybe i need to stop worrying ( on a budget if you get what i mean hehehe)

macca
 
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