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Join Date: Jun 2012
Location: Metro DC
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Arcing from the coil?

Hi Pelicans - I had a no-start situation with my Ď83SC this weekend. Strong crank, spark, and fuel pump running fine. I moved some of the plug wires at the distributor and got the engine to fire. But...

Running kinda rough, and I heard a crackling noise...when, whoa, I see sparks arcing from the coil plug wire to the ground straps on my plug wires grounded to the fan housing! Turned the engine off quickly (multiple cranks had likely flooded the engine, didnít want to go boom) and moved the ground wires as far from the coil plug wire as I could. Restart just fine, smooth running the rest of the weekend.

Has anyone encountered this before? Plug wires are less than a year old, Beru. Coil is silver, I do have my original as a spare. Whatís the fix here?
Old 09-22-2019, 05:32 PM
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Originally Posted by garment View Post
Hi Pelicans - I had a no-start situation with my Ď83SC this weekend. Strong crank, spark, and fuel pump running fine. I moved some of the plug wires at the distributor and got the engine to fire. But...

Running kinda rough, and I heard a crackling noise...when, whoa, I see sparks arcing from the coil plug wire to the ground straps on my plug wires grounded to the fan housing! Turned the engine off quickly (multiple cranks had likely flooded the engine, didnít want to go boom) and moved the ground wires as far from the coil plug wire as I could. Restart just fine, smooth running the rest of the weekend.

Has anyone encountered this before? Plug wires are less than a year old, Beru. Coil is silver, I do have my original as a spare. Whatís the fix here?
Old 09-22-2019, 05:37 PM
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The cause of "plug wires arcing over to ground" is always "insulation breaking down under load".

It could be that the wires aren't good, regardless of how old they are. If the old ones didn't arc, try re-fitting them.

Also, if the plugs are old and the gap opened up the resistance for a spark at the plug might be too high. Or maybe the plugs don't have a good electrical connection to ground through the threads in the head.

If it has the option of completing the circuit some other way, electricity will take the path of least resistance... That's what you're seeing.
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Old 09-22-2019, 05:53 PM
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Put your OE coil back on for starters.
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Old 09-22-2019, 07:04 PM
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Lash
 
Join Date: Oct 2012
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+1 what spuggy said

I use to turn the lights off in the garage, lower the hood some and watch the sparks fly from old worn out plug wires. Now we fight the battle with inferior components from over seas. You corrected the problem temporarily but if you did purchase a cheaper set of wires most likely the arcing will return.

Lash
Old 09-22-2019, 07:57 PM
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Get rid of those shielded cables. They do nothing as far as preventing air box explosions and are more trouble than they're worth.
Old 09-25-2019, 09:10 AM
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Night time is your friend when it comes to finding sparks under the hood.
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Old 09-25-2019, 10:21 AM
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