Oil
 

What oil should i use in my 12 hp Kohler? I know I should use 10W-30, but should I use conventional oil or synthetic?

All that information is in the Kohler K Series Service as found in our Technical Library Section.

run sae 30 oil in the summer and 10w30 in the winter unless your down south. a few years back the government was pushing the oil companies to remove zinc from the oil as its bad for the environmet, zinc is added to oil as a anti scuffing agent to keep parts like lifters from being chewed apart by the camshaft. zinc isnt required in newer engines that are full roller but older engine still need zinc. there was a chart i found once that had a breakdown of which oils had the highest zinc content and valvoline conventional was one of the highest and thats what i run and have had no issues. unless you have extra money i wouldnt run synthetic, it wont provide anymore longevity over conventional provided you change your oil regularly.