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Comment by derekp7 | Hacker News Reader

Not only that, but the last lawn mower I bought (with my first house) lasted me 20 years. Whereas I'm sure a lawn mower that is used 15 times a week wouldn't last much more than a season or two.

Off topic, but when I bought a new mower last year, I couldn't believe how far the technology has come. No more primer bulb, starts easily on the first pull, and a few other items I don't recall off the top of my head. Same with cars, for example if you get out of it while it is still in gear it automatically puts itself in park, and it can limp home with loss of coolant (it fires every other cylinder pushing air through the others for cooling).

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There are many different grades of mowers. A cheap residential mower is cheap and lasts just long enough that you don't think it was junk when you have to replace it. A commercial mower is used more in a month than most people mow in a lifetime and is built to higher quality (and price).

The neighborhood mower would cost 10x as much last just as long and serve the needs of 20 people - so a better deal in the long run. However what price are you willing to pay to not have to use the mower on your neighborhood's schedule - owning your own is probably worth it for you.

Do you have a reference for the car engine thing? I did a quick search and couldn't find anything yet. Sounds really interesting, I'd like to read more.

Ford has been doing this for decades (I think I saw it mentioned in the docs for EEC IV.) It turns off fuel for a cylinder here and there intending to pump heat out of the engine (a cylinder with no fuel is an air pump.)

It doesn't really let you operate with no coolant. Might get you farther before you die if you push it.

You are correct, that the manual doesn't specifically say it can operate without coolant (now that I re-read it). What it does is active fail safe mode, then will shut the engine off once the temperature goes above another (higher) threshold. So I guess if coolant is completely gone (instead of just low), you may be able to drive for a few minutes then be shut down for a while before driving again (the main purpose is to give you enough time to find a safe spot to stop).

Here is the owners manual for my car: http://www.fordservicecontent.com/Ford_Content/Catalog/owner... On page 259, under the heading "Fail-Safe Cooling".

  If the engine reaches a preset
  over-temperature condition, the engine
  automatically switches to alternating
  cylinder operation. Each disabled cylinder
  acts as an air pump and cools the engine.
  When this occurs, your vehicle still
  operates, however:
  • Engine power is limited.
  • The air conditioning system turns off.
  Continued operation increases the engine
  temperature, causing the engine to
  completely shut down. Your steering and
  braking effort increases in this situation.

> it can limp home with loss of coolant (it fires every other cylinder pushing air through the others for cooling).

Wow, this really cheered up my morning. Thanks.

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