JD SX 85 coil movement

runandrise

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Greetings all. I’ve had my Rider a few years and have gotten enough help that I got it running. My newest problem is I can’t keep the coil gapped! I double a sheet of paper for my spacing after loosening the two bolts that hold it in place. After retightening, and now I have lock washers under the heads of the nuts, it’s still making contact with the flywheel. I can tell immediately it moved, because it usually starts pretty good. If not, I put in my spark tester and no spark. Then I remove the cover, which is pretty quick these days, sure enough, just one “outer” edge of the coil is making contact. Is this indicative of a bad coil, or I need a better trick to hold It tight in place. I’m REALLY hesitant about breaking these very small bolts by over tightening, and I feel pretty confident they are snug…
thanks!
 

Rivets

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If it came to me with this problem, I would do the following.
First I would remove the coil.
Second I would carefully sand the two mounting posts flat and square.
Third I would install the coil using a small dab of BLUE Lotite.
Fourth I would set the air gap to .018”. When I don’t have my feeler gauges handy I use a business card.
Fifth I would snug the bolts as tight as I feel comfortable with.
Let sit for 24 hrs. Test the unit.

The only other thing I do is clean both the bolts and holes with a tap and die, but most people don’t have them down to that size or are a little scared they might ruin the threads.
 

StarTech

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Briggs 28M series

Air Gap .010 - .014" Screw torque 30 in-lbs.

20 lb Bond paper is .0035 so when folded is only .007".
 

ILENGINE

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Had that issue a few years ago on a Honda. The issue was the top bearing under the flywheel was damaged and allowed the crankshaft to wobble and get closer to the coil when the magnet came around.
 

runandrise

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Appreciate the replies guys. Definitely good advice. I’m doing the easiest first. The paper was a YouTube video. It worked initially, but…..
thanks again!
 

runandrise

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Being one that likes to report back on results, I’m happy to say that after sitting for a month, the JD started almost instantly. I used the Rivets method. I did all the work, but left for Tn. The next day for 3 weeks. Was very pleasantly surprised how quick it started. I barely turn the ignition key and it’s running.
thanks again for all the advice!
 

Rivets

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Thank you for letting us know the results, most guys won’t do that.
 
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