Help pick the best type oil and viscosity for my two air cooled vertical shaft OHV Kawasaki engines. Both engines use full pressure lubrication with an oil filter (AC Delco 1233 or Kawasaki 49065-2078). The first is a 6.5HP 179cc single on a 21 inch Toro commercial mower. The second is a 23HP 680cc v-twin on a 52 inch Wright Stander. The Engine Manual permits both 30 weight and 10w-30/40 API SF,SG,SH,SJ service classification oil in the temperature range I will use them(40 to 95 degrees F). I currently use Mobil 1 10w-30 in the single and change oil each 25 hours and filter each 50 hours. Looks clean when I change it. Notice a slight oil consumption of 8 ounces between 25 hour changes which manual indicates to expect some consumption with multi-vis oils. Dealer says to to Valvoline 30 wt in both as he does think 10w-30 M1 is as good for these engines. I not convinced dealer has high knowledge of engine oil though. Any thoughts. My direction is to use the best oil that will keep engine alive for long life and keep internals clean. The only 30 weight synthetic I know of is Amsoil 30 and not to offend am not sold on the brand. Would consider HD Diesel oil I use in my Duramax (Delo 400 15w-40) but that visicosity is not given as a grade choice for either engine.
Any thoughts would be appreciated.
Thanks
Slick
Any thoughts would be appreciated.
Thanks
Slick