p.s. The 'Owners' Guide' continues on to say the oil in the timing case should be drained at the same time, flushed, and refilled with 1/4 pint of oil. Following this 1000-mile procedure the oil supply screw should be turned fully on (i.e. the air screw turned all the way in) and the engine run "gently until the exhaust gas becomes blue..." How long will I have to run the engine before enough oil has accumulated in the bottom of the crankcase for that to happen?cmfalco wrote: Page 16 of the 1928 'Owners Guide' says to drain the crankcase every 1000 miles,
There are approximately 20 drops of oil in a ml so at the "normal" rate of 10-20 drops/min. that's ~0.5-1 ml/min. Some fraction of that is burned (what fraction?), but once the crankcase is full to whatever level where the breather starts expelling it that means when steady state is reached ~0.5-1 ml/min. will be dumped on the road. What concerns me is that mine left behind more than a few ml on the driveway every time I stopped for a few seconds. Later I drained 80 ml from the crankcase but, if no oil were burned, even at a rate of 0.5 ml/min it would take less than three hours to accumulate that much. At an average speed of 25 mph that's less than 75 miles, which is far less than 1000. Given this, and the fact mine dumped "too much" oil on the driveway, is what concerns me. If I do need to be concerned, why, and if I don't need to be, why not?
As an estimate, covering 1000 miles at an average speed of 25 mph would take 40 hours (2400 min). At the above flow rate that means the oil consumption will be ~1.2-2.4 liters/1000 miles so I need to plan for 10 l of oil for next year's 4000 mile trip.
