I'm confused as how you see a plug melt?

The balls of melted stuff that stuck around the center electrode. I assume that stuff is at least partially the remnants of the side electrode where it has worn away. Look at the pics and yu see that the side electrode is not square but kind of beveled above the center electrode as though it has been worn or melted away one tiny bit at a time.

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see that the side electrode is not square but kind of beveled above the center electrode

Exactly. But that's magnified. So you have to look at the metal to surface loss ratio. There is no way that each spark is going to pound a bevel off that, blow a chunk into a ball, no fucking way. Go back where I said it takes 1000's of hits to cause that, so you do the math times mileage, stopping, idling, etc. It adds up, but we are talking about it vaporizing when it does bite off a molecule or count how many are blasted off that, then look at a plug with low mileage and you can't even see a spec on the porcelain.

No, when we discuss those balls, to my experience, that says 'molten&many.' And those are large in proportion to the bevel around the center electrode. Not only that, it would have to be consistent and continue to eat away at the center and side electrodes, "equally."

I also noticed that bevel on the new plug: if where I think you mean? So imagine I cutout that side electrode so a pocket is formed. What lays in that pocket? More fuel to start the ignition to begin the 'flame front.' Flat side electrode is a wax thick kind of fuel layer. So that troth of liquid/air is also a consistent starter place too if you think about it.

We talking about the same pocket? I say machined away, you say the spark ate it away? I say rub both hands together and that means both contact points were equally eaten away. Your troth is way out of proportion of being equal in electrical eatery. Something huge had to ball up like that. And carbon does not ball on every fire. That is layer after layer covering the chamber over the next layer. Show me the ball in that.

And Grn, run dry plugs. Don't worry. Book is not.

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We talking about the same pocket? I say machined away, you say the spark ate it away?

I was speaking of the surface on the side electrode directly opposite the center electrode. Yes, the sides of the tip of the side electrode are machined away but the top and bottom are flat and square on the new plug's side electrode. My old plugs exhibit a slightly concave carved out bevel on the inside of the tip of the side electrode.

Where the balls came from is interesting to speculate on but the main concern is preventing them from breaking off and falling in the engine. If you change the plugs, you eliminate the balls. the longer you wait to change plugs, the greater the chance a ball or two will break off and go into the cylinder.

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If you get married, you eliminate the balls

Fixt it for you!

;D

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On a serious note, D; I scraped the electrode of #4 before I grit blasted it.

The deposit, whatever it's composition may be, was "crusty" and readily fell apart into granules when acted upon by a metallic probe. It had the behavior of saturated salt that was allowed to dry.

I believe the nodular appearance is due to the substance reaching it's melting temperature at that location on the electrode.

If piston crown damage wasn't a consideration, then the next higher heat range plug may present more self cleaning qualities.

* Last updated by: hagrid on 11/2/2015 @ 7:32 PM *

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Sounds like it's fairly harmless stuff if it crumbles easily.

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