Bill Boyd
Well Known Member
Worth the watch, IMO, Gasman. Thanks for posting that.
My Stihl stuff is still getting the 30 year old Pennzoil 2-stroke Air-Cooled 50:1 stock until it's used up. Hopefully they won't have hard feelings about being treated as second-best, but 2-strokes will always be the red-headed stepchild around here...
Clearly the home testing he does here isn't anything close to quantitative science. The line between okay and not okay to use in an engine is rather subjective even if we did have a way to quantify it. Acceptable wear rates, risk tolerance, and economics of maintenance versus overhaul would all (for me) factor into deciding how good an oil has to look to be serviceable. At the end of the day, cutting an oil can open and hitting it with a flashlight beam and a dairy wisk will require a very subjective guess as to what results are acceptable, so I'm not sure the video advances our best practices in the field even if it helps clarify the reasoning behind safe storage interval recommendations.
Storage in a sealed bottle and in an operating crank case are also in no way comparable.
My gut, for which I have no credible defense other than personal opinion and preference, is that my personal minimums for calendar oil change interval is closer to 12 months than 4, if the Hobbs doesn't hit 50 hours first. That's assuming I don't start with oil that's been years on the shelf before it's used.
My Stihl stuff is still getting the 30 year old Pennzoil 2-stroke Air-Cooled 50:1 stock until it's used up. Hopefully they won't have hard feelings about being treated as second-best, but 2-strokes will always be the red-headed stepchild around here...
Clearly the home testing he does here isn't anything close to quantitative science. The line between okay and not okay to use in an engine is rather subjective even if we did have a way to quantify it. Acceptable wear rates, risk tolerance, and economics of maintenance versus overhaul would all (for me) factor into deciding how good an oil has to look to be serviceable. At the end of the day, cutting an oil can open and hitting it with a flashlight beam and a dairy wisk will require a very subjective guess as to what results are acceptable, so I'm not sure the video advances our best practices in the field even if it helps clarify the reasoning behind safe storage interval recommendations.
Storage in a sealed bottle and in an operating crank case are also in no way comparable.
My gut, for which I have no credible defense other than personal opinion and preference, is that my personal minimums for calendar oil change interval is closer to 12 months than 4, if the Hobbs doesn't hit 50 hours first. That's assuming I don't start with oil that's been years on the shelf before it's used.