Do lawn mower engines get hotter than car engines?

They don't take coolant so I would think so.

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  • 3 months ago

    They are air cooled, so they may get a bit hotter, but they also don't generally run at as high RPM as car engines.

  • Anonymous
    3 months ago

    You think EHHH WRONG!  It is an air cooled engine. Some cars have been air cooled and most motorcycles have been air cooled and air plane engines are "air cooled" for many YEARS and many still are.

    . People always complained there was no heat in my Slug Bug (Type 1)VW Beetle.

    The engine is not made out of CAST IRON.  It is made out of Magnesium alloyed with aluminum because it cools faster than CI. Or some engines were aluminum with a cast iron sleeve where the piston slid.  It fits like a long sleeve sweater fits around your wrist...so very tight. Heat is transferred from cast to aluminum and that heat is gone into the air.  Not something you can remove as it is heat shrunk to fit one metal inside the other.  When the "pot" the name given to cylinders are wore out then you buy a new pot and swap them. By this time you should have done about 200K miles on that engine...so a hell of a lot of other stuff needs replacing.  That is what goes into engine rebuilding....changing the stuff that has worn out.

    . I have seen air cooled finned cast iron blocks on stationary motors(occasionally).  No extra longevity in doing that, just simpler to make.  It is the pour of one metal(cast iron). so heavier than SIN.

    . How cold the engines were was showing up in the oil filler neck cap.  A thick white or orange cream of moisture that has not been boiled off yet. Moisture that is in the oil and enters every night if you work days and sleep nights...like most workers.  You needed to drive 60MPH for about 30 miles to boil off the moisture(the cream is gone) and you need to do that daily.  Nobody does.  Yet the engines clicked over 100K no problem.

    . they do have THERMOSTATS TO control the engine cooling.  Too much heat leads to preignition or burning up of the piston.  That does not happen. They are that reliable.

  • 3 months ago

    You bet they do. Air cooled engines always run hotter than coolant motors.

  • 3 months ago

    they are air cooled

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  • Air cooled motors do tend to run a wee bit warmer than liquid cooled motors.

  • 3 months ago

    Most lawn mower engines are air cooled, but some larger riding mowers are liquid cooled. Smaller engines don't produce as much heat to need removed.

  • Anonymous
    3 months ago

    Yes but not hotter than a Motorcycle engine both are Mainly Air Cooled

    Villiers UK made Engines and Both Motorcycles and lawn mowers had the same engine

  • Anonymous
    3 months ago

    You might think the air cooled engine always runs hotter, but the fact is, they usually run at a constant rpm under a fairly consistent load in a relatively narrow 40-50 degree temperature range, where grass likes to grow.  Their cooling capacity is designed around this, and unless their fins are clogged with grass or the engine is out of adjustment, they stay pretty close to their designed operating temperature, relative to ambient temperature.  Cars operate in a much wilder environment, as much as a 150 degree or more temperature range, with equally wild variations in load and speed.  Liquid cooling helps it cope with this, but tow that trailer up a steep hill at highway speeds in 110 degree heat and you might be able to spot your exhaust manifolds glowing if you could see under the hood.  They run hotter still when they have a turbo.

    It's strange to me that there are some clowns here comparing air cooled auto engines to lawn mowers, you asked about mowers. In cars, air cooled engines are subjected to the same conditions as liquid cooled engines, a very wide range.  Because they don't regulate their temperature as well as a liquid cooled engine, they had to run with larger clearances to allow for expansion when worked hard. While liquid cooled engines big advantage is that they can extract more heat from areas inaccessible to air and thus have a much higher output in a tight engine bay, the main reason for their demise is their inability to quickly warm and tightly control their operating temp to help control emissions.

    Air cooled VW engines from the 60's produced a meager 30-35 hp/liter, had they put out more, they would have fried easily. Heater performance in the VW sucked because hot air from the engine in the back isn't easily pumped to the front where your toes are, it lost a lot of energy on the trip.

  • 3 months ago

    You're thinking of air-cooled engines, which have fins on the barrel to dissipate heat directly to the atmosphere, rather than liquid-cooled engines that have coolant circulating around them to carry heat to a radiator where it is then dissipated. Air-cooled engines can feel very hot, for that very reason. 

    Some larger mowing machines, especially some ride-ons, do have a liquid-cooled system. 

  • JJ
    Lv 7
    3 months ago

    I don't know about mower engines but i accidentally touched an car engine that was running and it was super duper hot.

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