Bought a 22 inch MTD mower off Craigslist for dirt cheap. Engine is 3.75 HP Briggs. Foam air filter element was missing and the oil looked like black sludge. Installed a new air filter, new plug, and filled with some 5w 30 PYB I had lying around. The mower runs very well but is probably sludged inside. I want to do two more oil changes at 4 hours each to desludge the engine and remove any dirt from the missing air filter. Which is the better cleaning oil, Supertech 30 WT HD, Supertech 10w30, or Supertech 15w 40?
Thank you in advance for any advice.
Thank you in advance for any advice.