tohatsu M40d

[brusky]

hey i am new to this forum and have been working on my tohatsu m40d it runs pretty rough. i have heard that this is pretty normal but the problem i have is that when it is at ful throttle it kinda backfires a little i think the carbs are out of tune it is a 3 cylinder with a card on each cylinder. i would like to start from scratch and get them as close as possible but im not really sure where to begin. i have worked with many vehicle carbs but never 3 at a time. can some one help me out with this?

[blared]

I would check the accelerator pump and the timing.