lazyuniondriver wrote:Rudi wrote:Personal preference for me was based on the recommendations...
Prior to our ease of internet access and the wide spectrum of test data uploaded for browsing covering every subject under the sun, a man could only decide what to preference by gathering information from experienced folks, respected elders, textbooks, or from their personal education and experience. Occasionally advice from some of the aforementioned may not have been reliable.
As an example, I was never able to convince my father the wind chill factor has no effect on cold weather starting. 20 degrees is 20 degrees no matter how fast the wind is blowing. The only effect wind has is blowing away heat you are trying to apply to warm things up. I know people who still would take my dad's side offering hours of debate about wind chill.
Can you believe everything you read on the internet? You have to consider the source of the information. Data submitted from testing laboratories and OE manufacturers' such as the B & S oil temperature chart you shared, I would regard as reliable.
I think I've mentioned this before, I like to learn one new thing everyday. I'm not afraid of changing a long time practice due to the discovery of new or updated reliable information. It's part of the learning process.
I am an evidence based person, if there is a real study that supports a course of action then that is the right course to follow. I do not understand why anyone would want to use straight weight oil or even worse, non-detergent oil, for an engine. Oil has changed a bit in the past 60 years. Putting 10W oil in an engine may help at low temps for starting but may be too thin once the engine warms to operating temps. Multiviscosity oils correct that problem.
I also do not believe everything I read on this or any other web board nor do I always believe what is written in a book. Try to determine if what is posted fits with the accepted science. The accepted science may still be wrong but is a good place to start.
Even though I believe in multiweight oils, a cub engine is not a Cummins. I expect the bearing loading is different and the cub may be a lot less likely to be damaged during startup. Old oil left over from the turkey fry may work in a cub engine but if you have to buy the oil you may as well use a modern oil.