Environment & Energy

taxi

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15. There have been advancements made in outdoor power equipment motors. Two ways are scavenging and stratification.

Sun Jun 15, 2025, 10:47 AM

Jun 15

Scavenging is clearing the exhaust gasses from a cylinder, and stratification adds passages to the intake side of a motor to allow a charge of fresh air into the crankcase. This reduces the amount of unburned mixture flowing through the motor.

The stratification of the fresh charge intake has a positive effect on engine performance parameters and reduction of the toxicity of exhaust gases (Fig 7.). ... Reduction in the direct losses of the fuel mixture by blowing is reflected in the reduction of emissions of unburned hydrocarbons CH from the exhaust gases by 25-30%. The content of carbon monoxide CO on the power mode is reduced by 1.5 times.

https://trans-motauto.com/sbornik/2015/1/03.A%20STUDY%20OF%20CHARGE%20STRATIFICATION%20IN%20THE%20TWO-STROKE%20ENGINE%20WITH%20GASOLINE%20INJECTION.pdf

There are some more advanced motors that operate without crankcase oil and require mixed fuel to run but have valves and operate on the Otto cycle.

In summary, no case can be made that motors of this type are a solution to excessive emissions, or that battery technologies are not the direction we need to promote. As advances are made consumers will make better choices.

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Emissions Test: Car vs. Truck vs. Leaf Blower (Edmunds) [View all] usonian Jun 14 OP

No Catalytic converters on the leaf blowers? pwb Jun 14 #1

Lol! It would skyrocket the cost of one. usonian Jun 14 #2

Lost in this discussion is Carbon Dioxide OKIsItJustMe Jun 14 #6

All my power tools are electric. usonian Jun 14 #7

2011 article? flvegan Jun 14 #3

Perhaps. I can't find a date on it. Does that matter? OKIsItJustMe Jun 14 #5

Offers some context. flvegan Jun 14 #8

I share your suspicion (i.e. that vehicle "emissions" have improved in the years since then) OKIsItJustMe Jun 14 #10

Speaking only for myself flvegan Jun 14 #12

Some years back, my (elderly) father got tired of fighting with his old gas lawn mower and wanted an electric OKIsItJustMe Jun 14 #13

Gas leaf blowers are banned in my area for air quality reasons. RockRaven Jun 14 #4

I always wondered . . . . hatrack Jun 14 #9

Yeah, but do you do it every week? OKIsItJustMe Jun 14 #11

That's interesting. I have a cordless electric mower with which I mow the leaves for mulch. NNadir Jun 15 #14

There have been advancements made in outdoor power equipment motors. Two ways are scavenging and stratification. taxi Jun 15 #15