ebinmaine 67,309 #1 Posted April 12, 2021 Folks I've got two engines here that I'd like to get new spark plugs in. One is a mid-70s Chrysler single cylinder military. The other is a 50s vintage Kohler generator with a twin cylinder engine. Plugs appear similar on the outside but I don't know for sure they are the same specs electrically. How would I go about getting the correct replacement? @Stepney @pfrederi Share this post Link to post Share on other sites
squonk 41,038 #2 Posted April 12, 2021 (edited) Are there any numbers on the old plugs? Some new plugs that fit the older engines, the terminal will screw off. https://www.ebay.com/b/Champion-Spark-Plug-Vintage-and-Classic-Car-Truck-Ignition-Systems/34205/bn_116852959 https://forums.aaca.org/topic/352200-early-spark-plug-reference-chart/ Edited April 12, 2021 by squonk 1 Share this post Link to post Share on other sites
ebinmaine 67,309 #3 Posted April 12, 2021 5 minutes ago, squonk said: numbers on the old plugs TBH I hadn't taken the time to clean them up well. One would think there would be numbers, yes. Share this post Link to post Share on other sites
squonk 41,038 #4 Posted April 12, 2021 Hope the numbers are still there. If not you might have to call around to parts stores to see if they still have a vintage Champion spark plug book there, or if they are real nice they could call Champion directly and let them figure it out. I've got a Napa vintage industrial ignition book here but there are no plugs in it. Share this post Link to post Share on other sites
peter lena 8,583 #5 Posted April 12, 2021 @ebinmaine, put any related plug info on the net , like google , you will quickly zero in on your answer, pete Share this post Link to post Share on other sites