smalltownguy2
Cadet
- Joined
- Jul 28, 2015
- Messages
- 6
Picked up a 1973 Johnson 65hp earlier this summer. Cleaned all 3 carbs, found 1 cylinder with no spark, bottom one. Moved the coil to the middle, and the "no-spark' traveled to the middle. OK, that's easy, just replace the coil, right?
Pulled off the coil, and put the rebuilt coil kit on. Spark returned on the middle cylinder, and full engine power restored. Yay!
Used the boat a few times, noticed that we were having trouble shutting the engine off with the key. Wasn't sure if I had a loose/broken wire at the switch in the throttle console, or back at the engine. Examined the console, too hard to get all the way in without serious disassembly. Decided to pull the engine cover to inspect the engine.
Found the bottom spark plug wire was pinched between guide pin of the engine cover and the guide bushing the pin goes into. It looks like the spark plug cable may have gotten in the way as I was putting the engine cover back on, and it got pinched.
I pull the wire out of the way, examined it for damage, didn't see any breaks in the insulation. Still have spark on that coil when dry-firing the engine.
But my engine still sounds and feels like it's only running on two out of 3 cylinders. No power under load. She'll start and idle on muffs in the driveway, but I'm at a loss in how I can correctly track down where the issue is.
If the pinched spark plug wire could be the problem, how do I get just a replacement wire only? I should be able to pull the wire out of the coil and replace it with a new one, right? My last repair (the center coil not providing spark) included the coil and the kit to "build your own" spark wire. I wasn't a big fan of that, I'd rather find something manufactured, rather than the DIY thing.
How to proceed?
Pulled off the coil, and put the rebuilt coil kit on. Spark returned on the middle cylinder, and full engine power restored. Yay!
Used the boat a few times, noticed that we were having trouble shutting the engine off with the key. Wasn't sure if I had a loose/broken wire at the switch in the throttle console, or back at the engine. Examined the console, too hard to get all the way in without serious disassembly. Decided to pull the engine cover to inspect the engine.
Found the bottom spark plug wire was pinched between guide pin of the engine cover and the guide bushing the pin goes into. It looks like the spark plug cable may have gotten in the way as I was putting the engine cover back on, and it got pinched.
I pull the wire out of the way, examined it for damage, didn't see any breaks in the insulation. Still have spark on that coil when dry-firing the engine.
But my engine still sounds and feels like it's only running on two out of 3 cylinders. No power under load. She'll start and idle on muffs in the driveway, but I'm at a loss in how I can correctly track down where the issue is.
If the pinched spark plug wire could be the problem, how do I get just a replacement wire only? I should be able to pull the wire out of the coil and replace it with a new one, right? My last repair (the center coil not providing spark) included the coil and the kit to "build your own" spark wire. I wasn't a big fan of that, I'd rather find something manufactured, rather than the DIY thing.
How to proceed?
