Waaay too much time on my hands.  I have the ultrasound machine out with the intention of blasting that recalcitrant float bowl to within an inch of its life to try and break up the crud that caused me so much heartache.

I looked at one of the poor NGK plugs on the bench that took the blame for my misfortunes for so long.  It is obviously a good, very lightly used plug, but fouled with soft carbon, oil and partially combusted fuel residue.

I looked at the ultrasonic bath...

Hmm.  Has no one tried it before?

In it went.  Warm water and a splash of detergent to swim in.

Fouled but hardly half an hours run time.


Splish splash I was takin a bath....


Fouling removed but the dog hairs are a new development.  Must have come from the rag I dried it off with.


So far so good.  No apparent ill effects. No path to ground, but there is a difference between 9v and 25kv. I will let it dry out a couple of days and then test it on a bike.  I have no idea how it will cope with hard carbon from a well used plug.
Any moderately used plug in a two stroke that I have had reason to remove tends to get discarded.

 

I did the same thing about a year ago. I had one of the original plugs from my CT-1 that was extremely dirty, and after about 45 minutes in the ultrasonic with a little detergent and vinegar, it almost looked brand new. it worked perfectly, however several months ago I noticed that it was corroding, whereas the new plugs I had in the other hole was not corroding. I don't know if that's a result of the ultrasonic bath,, or if spark plugs are more corrosion resistant now than they were 50 years ago. But the bottom line is it did work.

Yep tried it with mixed results, I have a sparkplug cleaner that uses blast media works great, the blast cabinet is the best, just make sure to clean out the little bits of blast media with brake cleaner and compressed air 

Lucky with the acid and sonic. Usually short out capacitance wise. Resistance  is OK but no fire.

Blasting is the absolute worst thing.

cliff