Spark plugs

[Everettlee]

My 782 with Kohler KT2 has Rv17 plugs in it
IF I looked correctly it should have RV12 plugs…
Has the previous owner screwed up or went hotter because it does burn oil?
Obviously I need spark plug education

 

[1811Cub]

You didn't specify the year, but the original specified spark plug for a KT17 series 2 was a Champion RV15YC, or RV15YC4. It was later revised to a hotter RV17YC for the KT17's and Magnum flat twins. A lot of guys also use Autolite 25 or 26 plugs. The 26 is the hotter plug. These engines are very low compression ratio so a hotter plug keeps cleaner longer. Unless the chambers are severely carboned up, you should never have a pre-ignition condition. Gap them to .025" as per the Kohler Engines service manual (1st photo). 2nd photo is from the Magnum service manual where they revised the gap to .035" and the plug data for the magneto ignition.