I have 8 NGK plugs with considerably less than 500 miles on them. The have become so fouled that the engine doesn’t want to start. (I have determined that this was caused by an extremely rich fuel mixture and I will change to smaller jets to take care of this). I’m thinking there should be a way to clean these plugs so they can be reused. What’s the best way to salvage them? Thanks.
I had a clapped out 4cyl flathead in an old jeep that would require cleaning the plugs every few weeks (daily driving) otherwise it would have a hard time starting on all cylinders. I just took a wire brush, cleaned it as good as possible, and then sandpaper. There's also tiny pneumatic sand blaster boxes meant for cleaning spark plugs that use a shop compressor to sand-blast the spark plugs. Popular a**** the 2 stroke dirtbike communities I think.
X2 on the spark plug sandblaster is the easy way. But you can also just manually clean with a wire brush, either hand or a wire wheel in a powered tool.
I place carburetor cleaner in a small plastic container and soak the combustion side of the spark plug for about 20 minutes then use the wire brush of my bench grinder to clean them up.
In the long ago past we used a pocket knife blade to s****e out the built up carbon from an oil fouled plug. Of course back then almost all "service stations " had spark plug cleaners. Ben
Back in the '60's, the gas station where I spent my entire childhood had the sand bag/compressed air spark plug cleaner. I used it many times to give new life (temporarily) to my rides. I've also used sandpaper, wire brush method. Used the 'wire type' feeler gauge to dig out carbon.
My plug blaster has either cinders or crushed walnuts in it, I haven't used it in so long I can't remember.
If you use the blaster/abrasive type, make sure the inner plug is clean, (blow out with compressed air) otherwise left over abrasive will fall in to the engine and can cause damage..
Spark plug sandblasters make the plugs...OLD..! ALL...things electrical things that are made to make...sparks, work their best with sharp edges !!! Fifth grade science book info . What does a sandblaster do...wears away those nice sharp edges, and makes them round...NOT good for helping sparks jump from one edge to another ! Fix the problem, and buy NEW spark plugs. Verify that the problem is excessive...fuel, or excessive...oil ! Mike
When I worked on motorcycles we used to burn the tip with a butane torch. You don’t have to cook it just warm it up enough to sweat out the chemicals and burn off the carbon. May not be the most technical but worked.
In our shop cl*** they told us that the wire brush left metal particles on the plug, which would create a direct path to ground. The abrasive methods sometimes left abrasive on the plug, which ended up in the cylinder. The preferred method was the good old propane torch. Works for me. .bjb
My German boss had a spark plug 'cleaner and tester'. It resembled the canvas bag compressed air one, only larger. And it had a clear gl*** panel you could look thru, and see the underside of the plug. There was a coil-activated plug wire, which was energized by a small motor inside, with a set of breaker points. I'd clean a set of plugs, then blow 'em out good, insert them in engine, and finish the tune up. One day there was this simple O.T. (1200 VW) that had a miss, I traced it quickly to #2 cyl., which I had first off checked compression on all...(good) Pulled that plug and put it on the tester: Full compression (compressed air) and lit up the spark. Wow! The Champion L87-Y was firing, but WAY up inside, thru a crack in the insulator cone! Firing right over to the inside of the threaded base of the plug... We had some brand new out of the box (same make & number) that were bad, called our parts house...Owner condemned his whole stock, sending them back to the jobber. We ran at the drags in '63, I had a 426 Dodge that dirtied plugs... My contemporaries said they soaked them in carb cleaner. I chuckled, recalling the spark plugs I had seen that leaked past the porcelain seals... (Carb cleaner??? LOL)
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