Best oil? High zinc?

GearHead36

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My search skills must be crap, because I can't believe this hasn't been asked before, but I can't find it.

Just watched a video that said that small engines should use high zinc oil. Is this true? That's the first time I've heard that. None of my engine manuals mention zinc. They all say use an oil with rating blah, blah, blah OR HIGHER. The "or higher" part includes modern oils that don't contain zinc.

So... Do I need high zinc oil? If so, what does the braintrust here recommend? I did a little searching, and didn't really find any good options. Most of the hits were racing oil or break-in oil, at $20+ per qt. I have to think that there's something cheaper out there that will work.

Some vintage motorcycles need high zinc oil, and some owners swear by Rotella. Would that be a good oil? 30W Rotella is under $20 a gallon at Wallyworld.
 

ILENGINE

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All of the lawnmower formulated oils are high zinc. So Briggs, Kawasaki, Honda, Kohler oils are high zinc, along with the aftermarket oils sold by Stens, and Kinetix oils, The Rotella gas rated oils may not be high zinc but the diesel rated oils are. Are they needed. Not really.
 

Scrubcadet10

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I run Kawasaki K-Tech.
I get it from the local Deere dealer for a little over $5 a qt.
 

GearHead36

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All of the lawnmower formulated oils are high zinc. So Briggs, Kawasaki, Honda, Kohler oils are high zinc, along with the aftermarket oils sold by Stens, and Kinetix oils, The Rotella gas rated oils may not be high zinc but the diesel rated oils are. Are they needed. Not really.
Thanks
 

hlw49

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Although zinc is a metal it is also a lubricant. It is good for the valve train. It also good for the hydro's.
 

GrumpyCat

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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.
 

Hardluck

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Actually zinc has been reduced in the new auto engine oils for EPA reasons but it should be used about 1200 if you can get it. You can always just change your oil sooner if you are concerned about loosing the TBN in you oils
 
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bertsmobile1

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So zinc is mostly needed for the cam lobes & followers
It does 5/8 of SFA anywhere else in a mower engine
IT is not needed because the scuffing forces on mower lobes is quite low
Try compressing a car engine valve spring with your fingers then try your mower .
 
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