'93 40hp MLHR Yam. 3 Cylinders, strange firing situation.

[spyeoman]

Hi this motor, new to me today, was only running on cyl #3. all three cylinders were receiving spark but #1 and #2 were not firing. cleaned out the fuel system. i then swapped the yellow # 3 wire to cyl # 1,(and vice versa) thinking #1 would come alive and #3 die. instead, #2 two started firing, and #1 and #3 were dead. i did nothing to the #2 set up. i'm kind of stumped for the time being. anyone with experience or suggestions?
thanks a lot, steve.

 

[spyeoman]

Re: '93 40hp MLHR Yam. 3 Cylinders, strange firing situation.

maybe the firing order would help

 

[cousinabe]

Re: '93 40hp MLHR Yam. 3 Cylinders, strange firing situation.

I would stick with the original order of the wiring. looks like cleaning the fuel did something.
you may want to try squirting some premix in the non-firing cylinders to try to isolate fuel/carb issues.

http://www.boats.net/parts/search/Yamaha/Outboard/1993/40MLHR/ELECTRIC PARTS/parts.html

 

[spyeoman]

Re: '93 40hp MLHR Yam. 3 Cylinders, strange firing situation.

Thanks for the reply cousinabe
i'm going back to work on it tomorrow, i still have a feeling it may be electrical but i'm definitely going to go through the fuel again.