Reply To: Rebuild kf7

[David Stanton]

Look again at that oil mix.  I doubt it says 10W30, as I don’t think multi-weight oils existed when that motor was built and 10W30 would have detergent additives (at least I’ve never heard of a multi-weight il that was non-detergent).  This is not an oil for outboards.  Back then the recommended oil was SAE 30 non-detergent oil, or Mercury Quicksilver oil, which I think just hit the market about when that motor was born or maybe a couple years later.  Today the oil to use is any outboard oil that has an industry TCW-3  rating.  I buy Walmart’s house brand in gallon jugs for about $15/gallon.  The 8 to 1 mix you mentioned is a safe mix, but unless you are using it on a hydroplane where it’s revving RPMs above max spec, with today’s TCW-3 oil,  My opinion is that 16 to 1 should work well.  I use 16 to 1 on my older KE-7 , but use 8 to 1 when on my hydroplane.  Gas/oil mix ratios are a hot subject so I hope this doesn’t start a mix ratio war on this post.  Ignore those who say Amsoil can be used at 100 to 1!