Mercury saltwater 150

[coralman]

One of my mercury 150s will on

One of my mercury 150s will only reach 3500 rpms while it acts like its missing or sputtering. Also when I throttle back on the other engine this one will loose its rpms back to about 2000 or so. Ran single it will only produce about 2900 at full throttle. Any ideas
Thanks

 

[tonyob]

"Mike,

It sounds like you a

"Mike,

It sounds like you are running on three or four cylinders. Check the compression, spark, and if they are okay, pull the carbs and take a look inside.

Topny"

 

[coralman]

"cleaned carbs today and compr

"cleaned carbs today and compression checks out and changed plugs , still a miss"