50 hp merc lost two clyinders

[jefa]

1986 merc 50 wont go past 2200 rpm, rebuilt carbs and cleaned fuel system, no change, checked for spark today, two cylinders dead. Can the coils be tested? or should I swap dead for live and see if problem moves?

 

[Laddies]

Re: 50 hp merc lost two clyinders

Which two are dead

 

[jefa]

Re: 50 hp merc lost two clyinders

counting from the top. 1 and 2

 

[fishingdan]

Re: 50 hp merc lost two clyinders

You have got my attention. I am having a similar problem, but mine started after I fixed a leaky carb. I don't think I have dropped any cylinders, but I need to check that out. <br /><br />Just curious, how does yours idle? Can you tell that it is running on 2 of 4 when it is idling? <br /><br />I had a rough idle, but top end was fine when I found the leak. I took the carb off, repaired the leak, reinstalled the carb and now it has no power on the high-end. <br /><br />I posted a new topic for my problem earlier. I will be watching this thread.<br /><br />Thanks

 

[jefa]

Re: 50 hp merc lost two clyinders

idle is ok and revs all the way up in neutral

 

[fishingdan]

Re: 50 hp merc lost two clyinders

hmmm...this is sounding familiar. I guess I will be checking for spark tomorrow. <br /><br />Thanks

 

[Laddies]

Re: 50 hp merc lost two clyinders

The engine will free rev on 2 cyls, with no spark on 1 and it'e either the stator or switch box, to tell which it is with no DVA, change the Red and red/white and the blue/ blue white wires on the switch box, if the spark changes from 1+2 to 3+4 you have a bad stator, if it stays the same you have a bad switch box -- Bob

 

[jefa]

Re: 50 hp merc lost two clyinders

Thanks Bob , will try today and report back. Jefa