Re: 1990 90hp force popping sound out the third carb.
Fill out the profile.Do a compression test.Should close on all 3.Any more than 10% post that.Then reset the air screws.
In the water, in gear,motor warm.Before you begin,1st turn the air screws in till they just bottom out(GENTLY) then out 1 full turn.Remember what each was set at and if it's way different post that.
Then reset them,turn each in till it starts to miss.cough,buck then out 1/2 turn.Repeat on the other 2.J
PARDON THE WRITING, FOR SOME REASON I CAN'T USE PARAGRAPHS. THE SENTANCE'S ALL RUN TOGETHER !!!Ethanol is messing up a lot .It's delaminating the inside of older hoses causing clogs in the carbs/injectors and fuel filter.
Oh yea DON"T buy any parts from boats . net Worst company on the net.