can't get passed 2000 rpm

[blackmax]

hi, I have an 86 Mercury Black Max 150. It didn't run all of last summer and now it won't let me go past 2000 rpm. I've tried changing the plugs, changing the fuel filter and a quick clean of the carbs...and still won't let me go. it idles fine and below 2000 it's smooth? I've notice that it's also running hot but not over heating... any suggestiong or Ideas is appreciated<br /><br /><br />thanx

 

[Laotzu]

Re: can't get passed 2000 rpm

When I had this problem my 3 cylinder 50 was running on 2 of three cyl. I could tell because one plug was blackened while the other two had tan deposits. Quick cleaning the carbs don't always do a good enough job. I had to remove the carbs and clean the bowl(s) good. <br /><br />Jerry

 

[dakk1]

Re: can't get passed 2000 rpm

Hey blackmax<br /><br />As Laotzu said, definitely could be carbs. I would also do a spark test. Easy to do to see if your getting fire on all cylinders. A compression test would be good while your there. I have the 1985 version of your motor and have dealt with the same issues. Could be a lot of things, hope it's something simple. If not, more extensive testing to follow. Good Luck and keep posting.<br /><br />Dave..

 

[MortenH]

Re: can't get passed 2000 rpm

Also check the fuel pump and the primer bulb. Especially the primer bulb can be a problem.<br /><br />-M-

 

[Kiekhaeferscurse]

Re: can't get passed 2000 rpm

Just a guess, but being as your B, Max uses a stator that is comprised of 2 groups of windings, the Low Speed stator creates current (for the ignition system) up to 2500 rpm then the high speed stator winding's take the job over. Use an Ohm Meter or a DVA to check your stator windings resistance or Voltages.<br /> Of course the stator is replaced as a complete unit....hope this makes sence & good luck