boscomantico wrote:
Sure, but then the better question should be: why does it need 6 quarts while other engines of similar design and displacement need only 2 or 4 quarts to run properly?
One more parameter is the thermal capacity of the oil reserve. In most engine installations, oil is required for engine cooling as well as for lubrication. Depending on the size of the oil cooler and the airflow through it the quantity of oil will vary. Less oil heats up quicker (which is usually good) but will get hotter (which may not be good). I can see this even in my car – between min. oil and max. oil level the oil temperature difference is over 10 degrees C.
At work our technicians want us to keep the oil level as close to minimum as possible. This drastically (according to them by a factor of 2-3) reduces oil consumption compared to keeping the level at max. Oil temperature is no factor in these engines because there is an oil/fuel heat exchanger. Hotter oil is beneficial because it will result in hotter fuel.
We do 25 hour oil changes and 50 hour oil and filter. Continental O200, past TBO, and hoping to make 3000+ hours. Quick drain, and we don’t need a tube, just a plastic container supported up to it. Screw-on filter conversion.
Maoraigh wrote:
We do 25 hour oil changes and 50 hour oil and filter. Continental O200, past TBO
Our Super Cub (90 hp Continental) from 1949 has no oil filter. The engine still lasts forever.
what_next wrote:
One more parameter is the thermal capacity of the oil reserve. In most engine installations, oil is required for engine cooling as well as for lubrication
The oil is also designed to be within a certain temperature range for proper lubrication, not too hot and not too cold or the viscosity will be off, and the oil pressure will be too high or too low..
We change oil (and filter, of course) every 50 hours on our C172S. The IO360 engine is now at 3100 hrs.
