Power losson 75 Merc

[cantwetalineenough]

Please help, My year old 75 hp Mariner OB 2 stroke (Mercury) is losing power when it warms up. <br /><br />The motor has 40 hours on it and recently had the carbs and fuel lines cleaned. After warming up it runs close to WOT then the power drops, like its running on two cylinders only. If I let it sit for twenty minutes it does this all over again. <br /><br />I understand motors well enough but I am very new to outboards. This seems electrical. Could it be one of the three coils? Could I diagnose this problem at home or should it be done on the water to put the motor under load. I just have the standard tools and a multi meter.<br /><br />How about running the motor in the complete dark, this worked for a bad coil on a old motor bike of mine.<br /><br />Please Help, the motor too new for me to spend a big shop bill!<br /><br />Kev

 

[greasemonkeyozi]

Re: Power losson 75 Merc

I have a motor simillar to yours and had the same problem. If you have a switch box, replace it. Even if its ok, its gonna need replacing sooner or later. Your coil pack should be ok if it works sometimes. I have learned that with ciol packs, they either work, or dont.