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#engines

2 posts2 participants1 post today

This is an 1987 sickle bar mower. It features a 3HP Kawasaki FA130D engine. I welded the handle ~10 years ago for the previous owner. They have no need for it anymore (but now I do) and it was stored for 5 years.

I filled the tires, swapped the oil (it was black but not too bad) and the spark plug and put in the correct air filter (previously featuring a way to small kitchen sponge...).

It turns over and "worked perfectly last time it was used".

Right now there is no spark and compression (from what I can tell from the pull cord) is not tooo strong. Looking into the spark plug hole its quite dirty in there.

So I need to take apart the generator/spark gap etc. and check what is going on there and measure compression to know if I need to clean/reseat the valves.

I am not sure how to check if the injection thingy works correctly. I guess I need to separate it from the engine to find the part that drives it. Hopefully it delivers gas...

Any suggestions? Anyone familiar with those #Kawasaki #engines?

#Trump suspended some sales to #China of critical US #tech, including those related to jet #engines, #semiconductors & certain #chemicals. The move is a response to China’s recent restrictions on exports of critical #minerals to the US, a decision by Beijing that has threatened to cripple #US #SupplyChains.
The new limits are pushing the world’s largest economies a step closer toward #SupplyChain #warfare, as the US & China flex their power.
#economy #inflation #recession
nytimes.com/2025/05/28/busines

A model of the Chinese-made COMAC C919 passenger plane in Shanghai last year.
The New York Times · U.S. Pauses Exports of Airplane and Semiconductor Technology to ChinaBy Ana Swanson

#TodayILearned that “lean engines run hot” in internal combustion engines is a myth. Lean engines run cool, just as rich engines do, because peak cylinder temperatures occur at the ideal (stoichiometric) air-to-fuel ratio.

The myth likely comes from car tuners that attempt to maximize power output from car engines. Because maximum power occurs at rich mixtures (i.e. low air-to-fuel ratios), tuners only operate in the “rich” side of the cylinder temperature curve, meaning that they never tune the car past peak, which means that leaning the mixture always makes the engine hotter.

Engines tuned for economy usually run lean (i.e. high air-to-fuel mixture), and engines tuned this way will run cooler than peak.

Continued thread

🇨🇳 Niobium-silicon alloy can withstand temperatures exceeding 1,700 degrees Celsius 🌡️.
Lighter than the nickel or titanium #alloys that are commonly used today, and with three times the compressive strength at high temperatures, #engines made of such a material would be able to reach speeds and operational efficiency that are impossible with existing technology scmp.com/news/china/science/ar

South China Morning Post · ‘Gift from heaven’: China astronauts develop super niobium alloy for aerospaceAn experiment conducted in space has helped Chinese scientists do the impossible – and it could revolutionise aerospace technology.

#engines nerds. I need a new alternator for an old boat. Most online are for modern cars with flat multi-vee belt pulleys. Are the tapered shafts normally made to a common standard so I could remove the pulley and fit the old vee belt pulley from the old alternator? Or are they all different to make life more 'fun'?

Continued thread

Efficiency gains from engines will still be vital for the industry.

The most marked change in the appearance of #engines could be the return of the open #propeller.

The design dispenses with the #nacelle
– the cover
– to allow for a bigger fan that offers more propulsive force.

Superficially, it will look like existing turboprop engines,
but with the ability to fly at Mach 0.8, or 80% of the speed of sound
– the same as current jet engines.

#CFM, a joint-venture between America’s General Electric and France’s Safran, has said that its open fan #Rise engine could theoretically reduce fuel consumption and carbon emissions by 20%.

The company says it can reduce noise, which put paid to a previous prototype in 1986.

It will still have to persuade regulators and passengers that the engines will be safe if a blade breaks in midair.

As well as radical changes to airframes or engines, manufacturers are constantly looking for ways to salami-slice #fuel burn via small gains.

#Winglets, the curved tips of wings, were first introduced in the 1970s in response to the then oil crisis,
mimicking birds’ wings to reduce drag.

The split winglets on the 737 family since 2014 can reduce fuel burn by as much as 2% during a long journey, according to the Seattle-based manufacturer Aviation Partners.

(For plane-spotters, they double as the easiest way to distinguish a 737 from an A320.)

Birds have had millennia to evolve the ideal features for efficient flight,
so aviation designers have constantly used them for inspiration.

Airbus is experimenting with #gust #sensors on the front of the aircraft to register during turbulence,
with automatic responses from control surfaces of the wing,
similar to a bird’s constant adjustments to movements in the air.

#Concorde, which flew on only a limited number of routes, was the last passenger plane in service with a truly distinctive design.

The supersonic jet, which had swept-back, delta wings, was retired in 2003.

#Boom #Supersonic, a startup, is testing the technologies for a proposed “son of Concorde” with a similar look.

That plane would only ever be a niche service, flying 80 passengers at a time on premium routes.

But there is a possibility that Boeing and Airbus take radically different approaches to the workhorses that carry billions of passengers each year.

If the manufacturers go in different directions, then passengers might start paying serious attention to plane design, says Addison Schonland, an analyst who tracks the industry at AirInsight.

“I don’t think we’ve ever had a situation before, to look at an aeroplane and say, ‘that’s completely different’,” he says.

“How will people react to seeing those novel shapes?”

(3/3)
#Airbus #JetZero #Delft #University #McKinsey #fuel #efficiency #Boeing #truss #transonic

#SpaceX will not attempt to recover the #booster on this flight. #Starship 🚀 is expected to make a high-velocity splash down about 225 km north of the Hawaiian island 🏝️ of #Oahu. Starship will not reignite its #engines upon atmospheric reentry, nor attempt to make a #controlled reentry into the ocean 🌊. arstechnica.com/science/2023/0

Presumed Lift Off Time 📆 April 19 2023

Livestream : youtube.com/watch?v=L5QXreqOrT

Ars TechnicaGreen light go: SpaceX receives a launch license from the FAA for Starship"So far they’ve done what they need to do with regard to environmental impact."
Continued thread

Meanwhile, the #EU deal to phase out #ICE #engines by 2035 is put at risk by a lobby group who insist #EFuels can keep ICE engines going. But e-fuels are expensive and scaling them up is problematic.

"Big #auto component suppliers in Germany such as Bosch, ZF and Mahle are members of the eFuel Alliance, an industry #lobby group, as are oil and gas majors from ExxonMobil to Repsol."

IOW, the #FossilFuel industry once again in the way of a clean future.

reuters.com/business/autos-tra

ReutersExplainer: What are e-fuels, and can they help make cars CO2-free?Germany has declared last-minute opposition to a landmark European Union law to end sales of CO2-emitting cars in 2035, demanding that sales be allowed of new cars with internal combustion engines after that date if they run on e-fuels.