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93 Johnson 120 Spark Issue Help Needed

B

Buck-eye hunter

New member
I have a 93 Johnson 120 that has a miss at idle and will stall at times. I took the boat to the lake and the boat seems to be fine at wide open throttle. So far things I have done are:
1. I did a spark test and have spark at all cylinders that jumps 1/2" on spark tester.
2. Changed Spark plugs.
3. Did a drop test by pulling one plug wire at a time, no change in motor when wire is pulled from #1 can see spark jump between wire and plug when putting wire back on.
4. Marked TDC on the flywheel for all cylinders. Hooked a timing light up and checked timing on each cylinder. When hooked to #1 I do not see #1 I see #3. When hooked to #3 it is showing #3. When hooked to #2 or #4 I see #2 & #4.
I never see a signal or flash for #1.

I do not have a DVA adapter yet to test. Any ideas on what is causing this problem?
Thanks
 
I was thinking that, but I think I would have noticed the spark jump. I only have a single spark tester to test 1 wire/ coil at a time. I had good spark on all cylinders and I did not notice any spark jump while doing the spark test. . It makes me wonder if the power pack is sending spark to both cylinders at the same time. A spark tester that does all 4 at once would help there. I had good spark on #1 but when the timing light is put on 1 it flashes on 3. You never see a flash for cylinder 1 near TDC. Then when on 2 it shows 2&4 and when on 4 It shows 2&4.
 
Also I finally got a service manual and under indexing the flywheel, erratic ignition it says "The timing light should indicate that cylinder's number only, and the number should appear near the timing pointer. If another cylinders number appears, or the correct number appears more than once per revolution, verify wire and pin location on all timer base and power pack connectors, or replace the power pack. I am leaning towards the power pack, but I am looking for some advice from those that have worked on them, as this is my first v4. Thanks for replying, all help is greatly appreciated!!
 
Is this with the engine running, or when being cranked by the starter?
If when running, Quick Start should have time to shut down before you try any timing tests. Usually about 10 seconds if all is working right.
Also, if when cranking with starter, you must disable QS before you will get any real meaningful info from the timing light.
 
I figured the quick start advanced the timing some. But I let the engine run and could hear the engine speed change and noticed the rpms decrease on the tach. It has definitely puzzled me, especially having good spark on #1 then with the timing light on it you never see #1. It is frustrating but electrical problems usually are for me. Learning as I go though. All connections on the power pack looked good and correct wire colors.
 
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