Intermittent spark issue

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Cbrinker
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Intermittent spark issue

Post by Cbrinker » Sat Apr 20, 2019 4:13 pm

I finally got back around to working on my a5 2 cylinder after getting the 4 cylinder mule running and have an issue that is kind of stumping me on the 2 cylinder. It finally started up, runs pretty good and has picked up some compression after running for a while. The issue I am having is sometimes it will start right back up after I shut it off and sometimes it won’t, the times that it doesn’t I have checked for spark and there is no spark. I checked the ground for the ignition switch and it looks like it could possibly be the culprit because all someone did is strip back the end of the wire and pinch it against the front brace of the mule behind the witch with a rusty nut and bolt. The wire end is slightly corroded too. I figured I would check here to get other possible ideas just in case that is not the issue so when I get back to it in the morning I can check a few other things. I did clean the points before I even started trying to start it because it had sat for 15 years. Thanks

Chuck W.
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Re: Intermittent spark issue

Post by Chuck W. » Sat Apr 20, 2019 4:23 pm

I checked the ground for the ignition switch and it looks like it could possibly be the culprit because all someone did is strip back the end of the wire and pinch it against the front brace of the mule behind the witch with a rusty nut and bolt.
That might be the problem if you were unable to shut the engine down, it only grounds the magneto when the switch is in the "off" position. I'd be looking at the electric hour meter, sometimes they will ground internally and kill the mag. Try just unplugging it and see if that helps. Otherwise, may need to polish the oxidation on all the internal ground points in the mag.
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muleman7
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Re: Intermittent spark issue

Post by muleman7 » Sat Apr 20, 2019 8:40 pm

Heat can cause either your condenser or coil to stop working or your points base to loose ground and this can be intermittent.

Chuck W has a great post on building a mag with indications of making sure all mating surfaces are grounded. If I can find it I will post the link.
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markrdje
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Re: Intermittent spark issue

Post by markrdje » Sun Apr 21, 2019 2:29 am

I think I found it--MAGNETO SERVICE--12-11-12
change user name to mark

Cbrinker
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Re: Intermittent spark issue

Post by Cbrinker » Sun Apr 21, 2019 6:02 am

Ok, thanks guys. I can always shut down the engine, so I guess that is not the issue. It will do it if it’s hot or cold so I am thinking it is not inside the magneto, but I will check it again. I will unplug the hour meter and use the mule for a while, shut it down and restart it a few times to see if the issue is resolved. I had the magneto apart a couple months ago and cleaned everything like his Chuck W. ‘s post said, but it can’t hurt to recheck it.


muleman7
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Re: Intermittent spark issue

Post by muleman7 » Sun Apr 21, 2019 7:28 am

This is the link to Chuck W's great post on Magneto Service

viewtopic.php?f=79&t=214502&p=1257289&h ... 2#p1257289
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Cbrinker
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Re: Intermittent spark issue

Post by Cbrinker » Sun Apr 21, 2019 7:16 pm

Unplugging the hour meter didn’t fix it so it looks like the magneto is coming back off when I have another chance to work on it. Thanks for posting the link to his post about servicing the magneto.

Chuck W.
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Re: Intermittent spark issue

Post by Chuck W. » Sun Apr 21, 2019 7:41 pm

try one more thing, completely unplug the wire from the magneto. If there is an intermittent ground between the magneto and the switch, it could cause this. You'll have to either use a ground jumper wire or plug the mag wire back in to shut it down!
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Cbrinker
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Re: Intermittent spark issue

Post by Cbrinker » Mon Apr 22, 2019 1:03 pm

Ok, will do. Thanks

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