How do these plugs (high res pictures) look?

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These Motorcraft SP-493s have about 50,000 miles on them. Replaced them with one range colder SP-500s:

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photo-2.jpg
 
When I viewed the image 1, 3rd spark plug from the left seems to have had pre-detonation and electrode wear compared to the other plugs. Did you label the plugs relative to the cylinder?

With the insulators all that discolored, heat seems to be somewhat of an issue. Not sure if cooler running plugs will help, if it's truly a heat detonation thing.

I gave some random thoughts your way in the mechanical thread about this app.
 
You don't need colder plug, because mostly looks OK (5-8 from left). I think what you may want to try is to add injector cleaner, and check again after 1K.
 
Hello, The plugs "look OK" to me, but I have questions and comments. 1) The gap seems large. I'd guess they're around .070". I know there were high energy systems which had larger gaps, but not that big. 2) Are the insulators discolored or are they merely a bit greasy and have dirt on them? By the look of the body of those plugs, it took time to rack up those 50,000 miles. Kira
 
Thanks very much for the input. These plugs were actually installed in May 2010, and I did have a few problems when I detailed the engine and water got into the coils...maybe that might have caused some discoloration, but much of it smears right now.
 
Based on the looks of the plugs and my experiences with 3 Panthers, I don't see anything really wrong with them. Not sure why you're going with colder plugs. I would close up the gap a bit though.
The only time I used colder plugs was on the 2002 with BOC tune and resultant changes to the factory programming (including timing) - I went with recommended 1 step colder plugs and 180 thermostat. The 2002 also had substantial mods that benefited from the colder plugs, the 2003 and non-listed 95 P71 used standard range plugs.
 
I see a few deposits (might be from the cocktail of additives you use....
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But my bigger concern is the amount of rust on the plugs, indicating that water is getting down past the boot/coil seals.

Here are mine from the Expedition with about 75,000 miles on them:

expieplugs13.jpg


You can see I had a similar problem on #6 as you do on all 8.

Here is the boot from that cylinder:
expieplugs09.jpg
 
Kind of tough to tell the condition of these plugs with the photos here, but you can do so readily enough with these spark plug reading guides:
http://www.motorcycleinfo.co.uk/resource...g_condition.jpg
http://gasolinegirls.files.wordpress.com/2011/10/spark-plug-reader-chart.jpg
http://www.motocrossgear.com/wp/wp-content/uploads/2011/12/plugdiag.jpg
http://www.aa1car.com/library/reading_spark_plugs.jpg

Surprisingly, the "rust stains" on plugs are actually "corona stains" caused by oil vapors burning onto the ceramic, a common, harmless phenomehna that has no impact on plug performance.
http://www.densoiridium.com/howtoreadusedplugs.php
http://www.sparkplugs.com/sparkplug411.asp?kw=Corona+Stain&mfid=0
 
Originally Posted By: TC
Kind of tough to tell the condition of these plugs with the photos here, but you can do so readily enough with these spark plug reading guides:
http://www.motorcycleinfo.co.uk/resource...g_condition.jpg
http://gasolinegirls.files.wordpress.com/2011/10/spark-plug-reader-chart.jpg
http://www.motocrossgear.com/wp/wp-content/uploads/2011/12/plugdiag.jpg
http://www.aa1car.com/library/reading_spark_plugs.jpg

Surprisingly, the "rust stains" on plugs are actually "corona stains" caused by oil vapors burning onto the ceramic, a common phenomehna that has no impact on plug performance.
http://www.densoiridium.com/howtoreadusedplugs.php
http://www.sparkplugs.com/sparkplug411.asp?kw=Corona+Stain&mfid=0



The rust I'm talking about is on the metal body of the plug, not the porcelain. This is indeed RUST. A quick look at the OP's plugs compared to the ones from my Expedition show this to be the case and indicates that the plug boot seals below the coil are leaking water down into the plug wells.
 
I'm not convinced that what I'm looking at with Falcon's photos is rust on the steel shells. It looks more like a baked, oily grime to me. The plug on the extreme left is clean where the spark plug socket rubbed against its shoulders, whereas I suspect rust would not be so willing to dissappear so easily. Falcon stated, "much of it smears right now." Grime smears, rust...not so much. I've pulled plugs before that did have a dry, powdery reddish-rust-colored deposits on them that were....rust. Not saying there's no rust there....but grime? Yes.
 
^Falcon stated that in regards to the insulator not down on the threads, the insulators 'smear off', as in oily vapors which escape over time, right?

AFAIK, OVERK1LL is saying the threads into the head seem to be rust-ish.
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Originally Posted By: ltslimjim
^Falcon stated that in regards to the insulator not down on the threads, the insulators 'smear off', as in oily vapors which escape over time, right?

AFAIK, OVERK1LL is saying the threads into the head seem to be rust-ish.
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And the metal portion of the body of the plug, not the porcelain.

There shouldn't be any grime or anything on these plugs, are they are located in 6" deep plug wells, isolated from the elements by the COP boot seal. Usually, the only thing that gets by that seal as it degrades is water.... Which of course causes rust. If he's washing his engine semi-frequently, and the seals are bad, that will cause the plug bodies to get wet.... and rust.
 
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