Spark plugs

[201Steve]

Hey guys,

I pulled a couple spark plugs for inspection today. They looked good on visual inspection, but I found on 2 bottom plugs that there was some accumulation down in the hole of the plug, near the base of the electrode. It was kind of built up between the wall and the electrode base. It almost appeared a brownish/orangish color and was hard. I tried to take picture but camera wouldn’t focus. Any suggestion what it may be? Thx

[carusoam]

There is a graphic chart provided by one of the spark plug companies that has pictures and explanations of the various oddities that can occur with plugs...

Lead has some colorful skills for generating different colors...

Best regards,

-a-

[N201MKTurbo]

It sound like lead oxide. There are tools for removing it. It is not unusual.

I put these in a pin vise handle. I find it works better than the vidrator.

https://www.aircraftspruce.com/catalog/topages/championcutter12-01147.php

[DXB]

I use a cheap metal dental pick from the drug store - I think it's good enough for use when doing my own spark plug maintenance between annuals. Probably should get one of the vibrator tools though. 

[EricJ]

The brownish/orange stuff is sometimes accumulated silica from dirt/sand.   If the usual abrasive cleaner with compressed air doesn't get it out you can pick it out with a tool.   Just be careful to not damage the ceramic around the electrode.

https://www.aircraftspruce.com/catalog/topages/1201684.php

Some people use these, which is basically a small electric jackhammer to get the nasty crap out:

https://www.aircraftspruce.com/catalog/topages/t560sparkCleaner.php

[RobertGary1]

Are you making sure that during taxi youre pulling mixture back to the point of almost killing the engine? Taxiing around with rich mixture will fill the plugs with lead balls.  
 

-Robert 

[Yetti]

9 hours ago, EricJ said:

The brownish/orange stuff is sometimes accumulated silica from dirt/sand.   If the usual abrasive cleaner with compressed air doesn't get it out you can pick it out with a tool.   Just be careful to not damage the ceramic around the electrode.

https://www.aircraftspruce.com/catalog/topages/1201684.php

Some people use these, which is basically a small electric jackhammer to get the nasty crap out:

https://www.aircraftspruce.com/catalog/topages/t560sparkCleaner.php

Man that looks like the one from Harbor Freight

https://www.harborfreight.com/pneumatic-spark-plug-cleaner-32860.html

 

[Hank]

I swear the one I used to borrow was someone's old engraving tool withnthe curved tip stuck in it

[RobertGary1]

2 hours ago, Yetti said:

Man that looks like the one from Harbor Freight

https://www.harborfreight.com/pneumatic-spark-plug-cleaner-32860.html

 

That’s the one I use. Works great.  

 

-Robert 

[EricJ]

5 hours ago, Hank said:

I swear the one I used to borrow was someone's old engraving tool withnthe curved tip stuck in it

That's basically what it is.   I think aircraft tool supply, et al, sell just the attachment, too, and you can use it on an engraver.

https://www.aircraft-tool.com/shop/detail.aspx?id=PA01-21T

[201Steve]

Lead was my best guess. Thanks for the feedback!