1995 Evinrude Intruder 175HP no spark in one cylinder?

[bucknbass]

My engine seems to run OK but it's down on power and I can't get the RPMs up like I used to. I replaced the plugs not long ago and the top spark plug on the port side still looks like new but the others are wet, including the threads, and the porcelain is a little discolored in a brown color. The problem plug looks almost like new, just a little wetness on the plug, nothing on the threads and the porcelain is black on the sides, not opaque brown like the others.

I did a compression test and that cylinder is fine. Wasn't sure if I have a spark/electrical issue or a fuel deliver problem. It's not the plug wire because I switched another one with the affected cylinder and nothign changed.

Anyone else seen this?

 

[Cofe]

Re: 1995 Evinrude Intruder 175HP no spark in one cylinder?

Check the suspected cylinder for a strong spark. If it is a weak spark, (not like the other cylinders spark) then I would strongly suspect a power pack problem.

 

[bucknbass]

Re: 1995 Evinrude Intruder 175HP no spark in one cylinder?

Thanks, I'll look at it tonight. Wasn't sure if a bad power pack would affect just one cylinder or not.

 

[jonesg]

Re: 1995 Evinrude Intruder 175HP no spark in one cylinder?

swap the bad coil around with a good one, see if the problem follows the coil.
Do same with coil wire and sparkplug, keep track of which one is which.
Examine the coil when its off, clean coil ground mounting and look for cracks in coil potting on back and bottom, little cracks are the problem.

It COULD be the pack but eliminate the other components first.
(they're cheaper).