ojh, Thanks for the "tutorial" on spark plugs. I was the one who asked for it. Great explanation. You never get too old to learn something.
BTW, on the old 2 cylinder John Deeres, some people use 2 washers under them, instead of 1. Guess this would take up some threads and move the plug up some.........


57 GMC LCF 370
55 John Deere 40-W
59 John Deere 430-W
2000 GMC 4x4
56 John Deere 420-W
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