My Spark Plugs

[JHZR2]

Hi,

I replaced my spark plugs after 30k or so, as PM... I kind of think that I don't need to...

Here are all four:




From the back of the engine (nearest the firewall, not sure of cylinder number):








This bottom one is the frontmost cyllinder.  

Two look dry, two look wet.  The threads on three of them look wet.  I know for certain, since I took them out, that all four came out of the engine dry and clean.  There was a bit of oil in the spark plug holes (time for a new valve cover and spark plug gaskets, I guess) that coated the electrode betwen when I took them out and when I took pictures.

Overall they look good to me.  They were all consistently colored, and there were only minimal deposits on the outside of the electrodes, none on the center electrode.

All came out very easy, no issues.  

Any thoughts?  I suppose I could have gone much farther, right???

THanks!

JMH

[tjts1]

Spark plugs are cheap enough that 30k miles is a good interval even if they are not completely worn. When the edges of the tips of the electrodes start getting rounded off is when I consider spark plugs worn. Urs look to be just about there. You can't measure the plug gap on these like a traditional plug.

[JHZR2]

I have a wire spark plug gauge and found that I could set gaps using it, because the wire could fit or not by sliding between.

OEM from NGK are slightly overgapped, but its the difference of maybe 0.003"

JMH