Spark Plug Cleaning

Reader Contribution by Staff
article image
by Dave Irey

55/4/1: Modification for cleaning small spark plugs

I build, collect, repair and display model gas engines. One of my pet peeves is spark plugs, the very small ones are over $30 each, plus shipping. I had a small Bull Duram spark plug cleaner left over from my auto shop days. However, the top hole where the spark plug goes is way too big. The top where the spark plug goes comes off with four machine screws. I had a gasket package from my local hardware store, Jerry’s Do It Best Hardware, and a piece of thick rubber gasket was in the kit. I cut out a piece the same outer diameter as the old one with a small center hole. The grit for this type of cleaner is available in three grits, I use the finest of the three. This also taught me to run these small engines fuel mixture as lean as possible, so as to lessen spark plug fouling. This type of spark plug cleaner is available from several vendors. I am looking for unfinished model gas engines.

Dave Irey
Edina, Minnesota

Thank you, Dave, for that handy tip on how to adapt a spark plug cleaner for use on model-size plugs. For those of you not familiar with a pneumatic air spark plug cleaner, it functions attached to an air compressor set to 90psi. Simply insert a used spark plug, electrode side down, into the rubber cover of the spark plug cleaner. Press the trigger to use compressed air, or for increased cleaning, change the setting to use air and an abrasive mixture — “grit” — around your spark plug. The abrasive material is preloaded into the lower reservoir in the body of the cleaner. You may want to use compressed air to blow away residual abrasive material before reinstalling. — Editor

Please send your questions and comments for Flywheel Forum or your contact information for GEM Experts to Gas Engine Magazine, 1503 SW 42nd St., Topeka, KS 66609-1265 or email

Gas Engine Magazine
Gas Engine Magazine
Preserving the History of Internal Combustion Engines