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spark issue on Johnson 1974 4hp weedless

H

Hunter1069

New member
I was running my 1974 4hp weedless in a duck marsh last fall. Coming out I dropped one cylinder (half power). So far I have replaced coils, condensers, and points. Still no spark in bottom cylinder. I put the old coils back in, still no spark in bottom cylinder. I switched the old coils (side for side) and still get spark only in top cylinder, so the old coils were fine (each one sparks the top cylinder). This weeked I took the plate off and relpaced the plug wire and boot for the bottom cylinder, still no spark. Also tried a new set of spark plugs and same issue. Any other suggestions to figure out what is wrong with the bottom cylinder? I am out of ideas.
 
I did not swap the old condensers but put new ones in I ordered from MarineEngines. Also put new points in as well. The reason I put the old coils back in verses the new ones ordered from MarineEngines was the new coils were difficult to get in and allow the flywheel to turn freely. For trial purposes I put the old coils back in. I did have two new coils in and the lower plug would not spark with them either.
 
Clean the points. Even new ones need to be cleaned. Maybe I should say especially new ones. They probably have an invisible layer of non-conductive coating on the contacts.
 
I have not tested the coils. I wasn't sure which two places on the coil I should check and what to look for a reading. I am confident with replacing parts, but I don't always understand how everything works together. I have an ohm meter. Can you explain the place to connect and what the readings should be?
 
The new points were cleaned last fall when I installed them. The project was put on hold until last weekend when I replaced the spark plug wire and boot. I will try cleaning them again, but it didn't seem to make any difference last October when the new coils, points, and condensers were installed.
 
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