1982 Mercury 115 Thunderbolt issues

I just purchased a boat with this same wire broken in this pic. The last owner says the motor used to rev up under load and just quit one day and only revs to 2200 rpm now. Gaskets on fuel pump look newer as well as the gaskets on carb. I pulled plugs they look good have new ones on order. I drained fuel tank it was actually pretty clean. I changed some suspect fuel lines and installed an inline filter. Put it back in the water and still wont rev past 2200 rpm. In neutral it revs fine just doesn't under load. The motor sounds very strong when running around at 2200 rpm. Does this solid yellow wire have anything to do with my problem. I searched all over this motor and cant find out where it broke from. Any help would be appreciated. Im new to outboards but very familiar with 2 stroke motors. I'm at a loss here and getting frustrated.

Yellows are usually the charging wires. Suggest you download a wiring diagram and find out what's happening.

http://johnsoldmercurysite.com/whitepapers/merc1250/index.html

Should be similar IF yours ahs the same type ignition (distributor or ADI).


Jeff

http://www.maxrules.com/oldmercs/Wiring/1966ona/37.jpg Handy diagram

Thanks for the info guys. im just not seeing where this wire hooks to anywhere or what it should be charging. I tore all my covers off again tonight and searched high and low with no luck. I am wondering if any body has this same motor with the wire hooked up that could send us a pic.

Goes to the starter solenoid,idle curiosity,what is the number of your outboard? What type of connector have you? Comes back to Jeff's question,ADI or Distributor?

serial #6198495 ADI Put it in the water yesterday after new water pump install still no gain in rpm also isn't charging battery. Still haven't figured where this wire goes thinking it might have to do with charging system at this point. Boating season is coming to an end. Im thinking of just pulling carbs and doing a rebuild over the winter and trying for next season. Motor does idle when engine gets warmed up.

????----Those motors will run on 3 cylinders --------So the trouble shooting you need to do is first a compression test.------Then check for spark on all leads.-----Check for REAL spark and real sparks on those jumps a gap of 1/2" or even more.----------Have you found a wee device on your motor that is the rectifier ? ---It is used to charge the battery by changing AC to 12 volts DC for the battery.

compression test is 115 psi across the board. Motor sounds solid up to 22-2300 rpm then doesn't go any higher. Last owner says it used to run higher rpm then just quit and only goes to 2200 rpm. I haven't searched for the rectifier but assume its where the 1 yellow wire and black wires from choke go to ?

the picture I poster I think shows the rectifier with the 2 Phillips screws in it. Correct

That is funny.---------That is just a wee terminal block....--------Top of this page ---engine diagrams----See what a rectifier looks like !!!!!

Someone has removed the rectifier and terminated the wires.The number definitely makes it '82, and this is the wiring diagram for an '82 http://www.maxrules.com/oldmercs/Wiring/1966ona/37.jpg .High speed windings on stator on way out? Check both trigger and stator. Looking again at the pic you posted I suspect that someone has rewired this motor using non standard coloured wires,so where that wire goes is anyone's guess,but I still think it should connect to the starter solenoid,see the yellow/red to solenoid in the diagram.The yellow/black in your pic is supposed to go to the choke solenoid but seems to stop at that block as well.Where do those two black wires come from/go to ?Just reread earlier post,locate two yellow wires coming from under the flywheel and you should be able to find the rectifier