Hi,
that car and engine should get about 14 or 15 miles per gallon, as long as everything is in reasonable working order.
The plugs should not look wet or shiny with oil. Sometimes gasoline is mistaken for oil, though, as both can result in black or brown deposits. A properly running engine will cause the plugs to look a little grey, not black, and there will be no deposits or rough junk stuck to the plug.
As far as oil on the outside, or on the threads, it is very common for there to be a little on the threads, but not much.
You may have a problem with the carburetor, even if it's a "new" one. If there is too much gas going into the motor, not only will your mileage be poor, but the engine will use oil. The float inside the carb could be bad, or something else my be wrong or worn out.
Is the carburetor a 1-barrel or is it a 2-barrel? The first is about 20 cm tall and only about 12 cm across at the biggest point. The 2-barrel is only about 11 cm tall and is a rectangle with the outside about 20 cm by 12 cm. If you can tell me what is on the motor, I can give you a little better advice on what to check. Even if the carb is really a brand-new one, then knowing what carb will give me information on what other equipment the engine has on it.
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David
newbie #4153
