Good post!Zinc is the "synthetic" of lawnmower motor oil marketing hype.
ZDDP is a consumable lubricant of last resort. When contact pressure pushes through the oil film. When high lift, high speed, strong spring valves use solid tappets on camshaft, ZDDP is needed. Lawn equipment engines are not high lift, high speed, or use very strong valve springs.
All automotive motor oils contain at least 700 ppm of ZDDP. 1500 ppm becomes acidic so the "high zinc" oils are no more than 1200 ppm. This makes a difference if one is driving a 1969 Corvette fast with high lift cams that have not been retrofitted to roller lifter followers, and going more than 1500 miles between oil changes.
3600 RPM is not high speed. Valves one can depress with one's thumb do not have stiff springs.
Very few automobiles on the road have roller lifters. Have stiffer valve springs. Run faster than 3600 RPM. Yet they do just fine without excessive zinc.
Zinc is not the EPA regulated element, is the phosphorous in ZDDP the EPA doesn't like in catalytic converters and on O2 sensors.
Lets see some of those engines which supposedly failed for lack of zinc.
I have found that for the most part small engines are not picky about their oil used. So anything that normally would be used in an ICE will work fine in a lawnmower engine. Hydraulic lifters tend to require a thinner oil than solid lifter engines temperature pending. Hydrostat transmission and tractor hydraulic systems that use a common hydraulic, wet brake, transmission all use compatible oils.I've been running Mobil 1 synthetic 10w30 in my Kohler 27hp that's in a Grasshopper for years and had no problem.
I use this oil because I have it around for a vehicle I have.
Should I not use this?
Any oil is better than no oil. Jus' sayin'.I would say the only variance ive found with engine oil, SOME kohler commands i service develop lifter tick if i don't use the Kohler Branded semi synthetic oil.
Not if you run Slick50. Anybody remember the rigged commercials for it?Any oil is better than no oil. Jus' sayin'.
I am saying very few automobiles have roller lifters. My 2018 F-150 2.7 Ecoboost (twin turbo) does not. My 2016 9000 RPM Yamaha FJR1300 does not. My 2007 Prius did not. The valve springs are much stiffer than any power equipment engine I have seen. And while the Yamaha does over 4000 RPM quite regularly the F-150 rarely goes that high but will when pressed. The Yamaha has 85,000 miles, no valve adjustment, but I've checked. The Prius would rev to 4000 in certain situations.Good post!
HOWEVER ( ), you said: "Very few automobiles on the road have roller lifters. Have stiffer valve springs. Run faster than 3600 RPM."
I believe you probably didn't say what you meant to say there - that you would agree that most passenger vehicles built in the last 2 or 3 decades (and therefore most cars on the road today) have roller cam followers and all run faster than 3600 rpm. I feel sure we'd agree that production car engine valve springs are a good bit stiffer than those in most lawnmower engines (recognizing of course that "stiff" is a relative term, and that there's "standard production engine" stiff, and then there's much stiffer "competition/high perf" stiff).
A shorter (but maybe too direct) version of my post could be:
I disagree with "Very few automobiles on the road have roller lifters. Have stiffer valve springs. Run faster than 3600 RPM." Overwhelmingly most (all or almost all?) IC car engines on the road today have roller cam followers, stiffer (than lawnmower) valve springs, and run faster than 3600 rpm.
Cheers!
I remember Dupont suing over the use of their trademark Teflon™ while not purchasing from Dupont. Dupont refused to sell Teflon™ to Slick50 because Dupont engineers believed it hurt more than helped. Teflon™ breaks down in the combustion chamber. One of the components is HF, hydrofluoric acid, which is pretty strong stuff.Not if you run Slick50. Anybody remember the rigged commercials for it?