Adjusting the Spark Plug Gap

[OptsyEagle]

This may be another one of those dumb questions, but how does one reduce the gap of a spark plug? I have one of those round spark plug gappers and if my gap is to little, I use that little hole in it to bend out the electrode to the desired gap.

My question is for when the current gap is too large. Do you guys just press down on the electrode, do you put the gapper in between the electodes at the desired setting and press it until it touches or do you use a tapping technique. Is the plug held exactly perpendicular or do you try to bend the rounding part of the electode to reduce this gap.

I find the electrodes quite rigid and I am not sure the best way to reduce the gap when needed.

 

[Vic.S]

Re: Adjusting the Spark Plug Gap

I usually tap it with a small hammer. Sometimes I tap the plug on a hard surface.

It will be interesting to learn after 40 odd years or servicing my own cars and other engines if I have been doing something terribly wrong.

(The 8 COM plugs in my British Seagull outboards excepted of course because the earth electrode is to the side of the centre electrode)

 

[ezeke]

Re: Adjusting the Spark Plug Gap

I was cautioned not to strike a spark plug because of the risk of cracking the ceramic insulator. I have found that pressing the electrode into a fairly hard surface will get the job done.

I use one of those round Champion CT480 gauges to widen the gap.

 

[samo_ott]

Re: Adjusting the Spark Plug Gap

I have a gapper but I just tap it lightly on a hard surface.

 

[Randybeall]

Re: Adjusting the Spark Plug Gap

Been tapping spark plug ground electrodes on hard surfaces (vice,4 lb. hammer) since the middle 60's. No cracked insulators yet. I do own a gapping tool, looks like a big pair of pliers with a flat gap guage which fits into the plug gap. Squeeze to close up gap. I tried on a used plug once and applied lots of pressure till the center electrode slid down in the insulator. Care is called for.