I must be missing something here.
How do all the varnish causing agents know ahead of time I'm going to change my oil so they can avoid draining to the pan in anticipation of wreaking havoc in my engine? I'd like to get more of the used oil out of the engine, not less and I imagine a lot of it is clinging to the inside of a recently ran engine. Which to me means a long wait for it to get to the pan and I don't think that oil draining to the pan knows whether or not the drain plug has been removed from it. Seems to me that when the engine sits overnight, the amount of oil in the oil pan approaches maximum which would mean the amount of varnish producing agents and contamination left in the engine is at a minimum. Albeit we have thicker oil clinging to the smooth walls of the oil pan but I doubt the volume of that would compare to the warm oil clinging to the rest of the mostly rough cast block.
The only argument I can think of against that is that a recently ran engine has the maximum amount of contaminants suspended in the oil and not sitting in the bottom of the pan where they might not be carried out by the oil as it drains.
When you guys change it hot, how long do you really let it drain? Until the last drip, until it starts dripping instead of a stream, until the thick stream becomes a thin stream, OR, once you're done changing the filter and wiping the 15w40 out of your ear and armpit? I think I am going to try the last next time I change, hot, then put the plug back in and see how much oil ends up in the pan a few hours later.
Frame of reference alert: It doesn't really get COLD where I live so I have no experience draining oil wearing insulated carhart coveralls.
Not to single anyone out but Blackstone recommends a hot sample to "...help cook out any normal moisture or fuel build-up."
Anyone know how much oil is left in the oil cooler? Probably a waste of time worrying about ounces when there are pints that are never coming out during a change.
