firing order for mercury 90hp 4-stroke (2003)

[racingmom]

we are having trouble with a motor we just got, motor has been setting up for almost 2 years, and the people that had it didn't' take care of it. if anyone knows the firing order for this motor it would be greatly appreciated, or where i can find a manual online in a pdf format, that would help too.
the problems we have been having are:
idles. motor idels very rough,
2. 3000' get over 3000 rpm at full throttle,
3. motor feels like it's lagging

we have replaced the carb filter, plugs, and cleaned the carb

if anyone has anymore suggestions, help would be appreciated.

 

[HSEMJ]

Re: firing order for mercury 90hp 4-stroke (2003)

Not sure on where to get a manual in pdf format, sorry.
the firing order is 1-3-4-2. A rough idle could be dirty carbs or carbs out of sync. The carbs on these engines are very sensitive to the smallest bits of dirt. So unless your very sure the carbs are completely clean, i would go through them again. Also getting the carbs synchronized is very important for a smoth idle.
The lack of power could be a lot of things. Start with the basics, check compression, check spark, valve timing,
A service manual will be a big assett with troubleshooting, even if you have to buy one.
Hope this helps you.