Re: 64 Evinrude Sportwin 9.5hp firing on one cylinder
i just ran into the same problem w/ my '75 johnson 6 hp, but mine did not run rough it is not uncommon for these motors to run smooth on one cyl in nuetral. it stumped me pretty good! this is what i did, i replaced the plugs, wires and boots ( you will probably need 6ft or more spark plug wire, depending on the size of your flywheel), points and condensers, and the upper crank shaft seal( you might as well replace the seal while your in there because you have to remove the armature plate to replace the wires) all these parts only ran me about $45 but before you do any of this check the compression under optimal conditions it should be @ 100psi per cyl, but no mater what it reads more importantly it should be even any differance more than 5psi between cyl 's means there could be something wrong in the combustion chamber( scored walls, sticking rings, cracked pistons ect) the coils last a long time, im not saying thats not the problem, but usually there the last thing to go bad, but like the pevious post said i would definitly do a visual check of them any cracking or burning, replace em. hope this helps you it helped me. late!!!!!!!!!!!!!!
