1966 Johnson 6hp magneto timing issues

Crosbyman

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the critical issue with perfect timing is to have point open at the exact time . in the video the points are wired to a VOM and the markings are used to tell you when the points open when the markings line up.

this tool does the same and since Stevens testers are somewhat rare today a simple VOM or even a battery with a bulb in series connected to the points will work fine.

When the tool's pointy end lines up between marking the points must break causing the spark. .020 gapping is not that critical .Timed openning is !!
 

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racerone

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In the past I have developed blisters on my finger tips in explaining that the opening of the points is critical to get peak spark.----Actual gap does not matter , within reason of course.-----It is called a MAGNETO and it is a simple device that many folks struggle with.-----You can buy the entire set up ( 2 coils . points , condensers and wires ) for about $100 or less.----Just installed one set of breaker points on a 4 HP Mercury phasemaker.-----They were badly worn and needed replacement ----But that set alone listed at $125 US
 

440roadrunner

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Points are not used to change timing !-----This thing is a simple magneto and points are timed to get the STRONGEST spark.-----The timing of spark before or after TDC looks after itself with the linkages.---- The tip of the slow speed needle broken off by chance.----It is known to happen on those carburetors.-----The results of a compression test should be posted.-----The original head gasket has been replaced with a much better one.----Did you replace it ?
This is a mis-statement. The points opening DO time the mag, and can do so by several degrees. I use a factory timing fixture, set the points by timing, then double check gap. This check assures that something odd such as cam wear has not occurred. Why do you think "the book" talks about the timing in relation to the two timing marks---this variation is BECAUSE of allowable points wear, and if you set points at the first mark or just inside the two, they will wear "towards retard" as the rubbing blocks wear and CLOSE the gap
 

racerone

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Roadrunner I have repaired many of these motors !!-----I have those factory timer fixtures or I use the flywheel itself for timing with a meter.-----These magnetos are very very simple to me.
 

440roadrunner

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Roadrunner I have repaired many of these motors !!-----I have those factory timer fixtures or I use the flywheel itself for timing with a meter.-----These magnetos are very very simple to me.
Then unless I mis understood why you were trying to say, why are you seemingly negating setting the points to time rather than things like "strongest spark" or gap? The fact is, unless something is worn, broke, etc, when the timing is correct via the points, the gap will BE correct.
 

racerone

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When the points are timed correctly they open with the highest current . highest magnetic fields collapsing and results in the strongest spark.------This thing is called a magneto !-----Not the same as a 12 volt battery ignition system.----Note---- I learned how to repair these simple things as a young man in 1968.
 

racerone

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Actually I set the points by eye on a 1959 model 5.5 HP just to see if there was spark.--------Had spark.------Hopefully get the 11 year old grandson to do the final setting of the points using a meter and the flywheel this summer.
 
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