[Lobsta50]

I have a 1957 sportwin 10 hp Evinrude. Top cylinder will not fire.I have replaced coils and condensers and points.I did pull one condenser out to determine which one was good and found that both fired?????.I am baffled.Plug wires may be the problem but am having difficulty finding original spark plug wire numbers.

[WillyBWright]

They were cut from a roll. You just need to know how long and get some from a boat or lawnmower dealer.

[CATransplant]

If you pulled a condenser and got juice on both cylinders, check to make sure it was installed properly. Sounds to me like your shorting out that side.It's probably not the wires.