Date: Fri, 15 Sep 2006 13:01:25 -0400 From: Fred W <Malt_Houndnospamm-me-not*yahoo.com> Subject: Re: oil sludge?
darthpup wrote: > Your comments appear to stem from false theory. The problems I refer > to were confirmed by inspection of the lubricant at operating > temperatures. In one case the oil had become so thick that it > completely jammed the oil pump. > > MV oils increase their viscosity with temperature within and beyond > engine operation temperatures. A good single weight oil such as > Valvoline will sustain its viscosity with temperature. Thats why you > see so many race cars using the product. > There is no requirement for increased viscosity with temperature to > sustain proper lubrication. Actually, quite the opposite is the > requirement. > The polymer you refer to is an oxidizer which increases in chemical > activity with temperature. It has no way of limiting its activity and > OVER thickens the oil, per your observation of 10W50. > Nonsense. No oil, will actually increases in viscosity at any operating tempertures. They *all* get thinner as temperature increases. Multiviscosity oils only get thinner at a slower rate than single weight oils do. Sludge formation has nothing to do with increasing the viscosity of an oil. Sludging occurs when the temperature gets so high that it cooks the oil, permanently altering the chemical structure. This only happens at extreme temperatures, not those found normally in engines. But don't feel to bad, your misconception is a fairly common one. -- -Fred W