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Using an outside heater to heat car engine before trying to start on cold morning?

  1. Oct 5, 2009 #1
    Does anyone know the proper way to do this?
     
  2. jcsd
  3. Oct 5, 2009 #2
    Re: Using an outside heater to heat car engine before trying to start on cold morning

    You mean other than having a block heater installed in your car that you just plug in?
     
  4. Oct 5, 2009 #3

    BobG

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    If the car's sitting outside, the heat from the heater is going to dissipate. It will help a little bit, but not a lot. You would need well insulated blankets hanging from the hood to the ground, with the heater carefully located under the engine block, far enough away that the wind won't blow a flammable blanket into the heating elements. It's not a good way to heat your engine.

    As Georgina mentioned, an engine block heater will work much better. An oil heater or a coolant heater will work just about as well and are much easier to install. (http://autorepair.about.com/library/a/1e/bl119e.htm)
     
  5. Oct 5, 2009 #4

    Danger

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    While I have a regular frost-plug block heater, the one that I prefer splices into the cabin heater hose and circulates warm water throughout the system. It's cheap and really easy to install. Just make sure that you pick the right hose, aim the unit in the right direction, and leave the heater valves open. (Good link, Bob.)
    Given the climate around here, I also use an electric battery blanket and have a 1500 W cabin heater that I turn on a half-hour or so before driving. The latter not only makes for a comfy environment, but also deices the windows.

    Edit: Actually, the cab of the El Camino is so small that 10-15 minutes of the heater is sufficient. A regular car takes about 1/2 hour.
     
    Last edited: Oct 5, 2009
  6. Oct 5, 2009 #5

    DaveC426913

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    Hm. So I guess my method of hanging a 100W lightbulb in my engine when it's in the driveway is just foolin' myself.
     
  7. Oct 5, 2009 #6

    Danger

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    It's better than nothing.
    I thought that you were a fellow Canuck. :confused: Where I live, it can hit -45C. Even a heat-light such as for a sauna won't do much good here.

    Questionboy, also remember to bang on your hood a couple of times before starting the car. Otherwise, you might end up with a cat entangled in your fan belt. Strays like to sleep on engines in winter to keep warm.
     
  8. Oct 5, 2009 #7

    Astronuc

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    This is the method I used - and it worked - especially when the temperature was -20 to -30 F. I put a hang-light/lamp under the car. I put a blanket over the hood in order to insulate the engine. The blanket (or tarp) draped over the car such that it also prevented a breeze from blowing under the car.

    It also helps to use 5W30 motor oil or thinner in winter time.
     
  9. Oct 5, 2009 #8

    DaveC426913

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    I am the other type of Canuck.

    I'm in Toronto. I wear a black leather jacket and I get snow tires the day after the snowfall. If power ever goes out, I will die.
     
  10. Oct 5, 2009 #9
    Re: Using an outside heater to heat car engine before trying to start on cold morning

    And your mayor may call in the army to plow the roads.
     
  11. Oct 5, 2009 #10

    George Jones

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    But that man didn't last.
     
  12. Oct 5, 2009 #11
    Re: Using an outside heater to heat car engine before trying to start on cold morning

    Im only talking about -3 Celsius or 26Fareinheit here on an old car at worst and only at teh coldest part of the morning. The temperature will rise up to 20 Celsisus during the day. Like desert temperature in winter.
     
  13. Oct 5, 2009 #12
    Re: Using an outside heater to heat car engine before trying to start on cold morning

    Where is the exact spot under the bonnet I should put the bulb?
     
  14. Oct 5, 2009 #13

    mgb_phys

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    At non-canuck temperatures it's mainly the battery that's the problem.
    Block heaters stop the oil freeing at -40 but at -3 you are probably just loosing some battery power (especially if it's old).

    Easiest way is to wrap the battery in insulation, you can buy insulated battery covers in cold places but reflective foil covered building insulation material will work, it's cheap and fireproof.
    You could also add a garden heater, these are 6in square (or so) sticky pads used for keeping frost off planters in a greenhouse. They run off household current and take 20-100W depending on size.
     
  15. Oct 5, 2009 #14

    Chi Meson

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    It depends on the car, but a dipstick heater works well if the temperature doesn't plummet too much. Very easy installation, just replace the dipstick with this special one. Trouble is, the available kind doesn't work with some cars out there.
     
  16. Oct 5, 2009 #15

    BobG

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    You don't need any kind of engine heater at 26 deg F (-3 C). You don't even need a battery blanket. You need a new battery!

    mgb_phys is right that the blanket will allow you to spend a little more time with your current car battery, but it's really time to pull plug on the old thing if it can't withstand temps like that. Put it out of its misery and buy a new one.

    By the way, you do check the fluid in your batteries once in a while, don't you? Low battery fluid could case your battery to age prematurely. In fact, a leak could cause it to flat out die.
     
  17. Oct 5, 2009 #16
    Re: Using an outside heater to heat car engine before trying to start on cold morning

    A battery heater for -3C? Yeah, no, there's something wrong with your battery.
     
  18. Oct 5, 2009 #17

    Astronuc

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    Under the oil pan with the bulb close but not touching. In my experience, the whole engine compartment under the bonnet was quite warm, even when the car chassis was near freezing and the ambient air was at or below freezing.
     
  19. Oct 5, 2009 #18

    Borek

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    In good old days when I was driving http://en.wikipedia.org/wiki/Fiat_126 I used to put electric space heater (fan type) just under the bonnet :smile: 1.5 kW for 30 minutes and I was starting it even below -20 deg C.
     
  20. Oct 7, 2009 #19

    MATLABdude

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    Re: Using an outside heater to heat car engine before trying to start on cold morning

    That's the same thing I did last winter! Worked like a charm the few times I had to resort to it. My battery finally gave up the ghost after 5 years, and it had trouble starting when it hit -25 or -30 C, and gave up the ghost when it was -40. I got a new battery which I installed when it had 'warmed up' outside to around -30. Everything was numb, and I recall that the drop of drool or snot I dripped froze before I had a chance to wipe it away...

    In any case, when I was installing my battery blanket this summer, I think I leaked some of the acid out. Anybody know the best way to check the level, and whether I'd need to replace the sulfuric acid as well, or if I can just top off with distilled water?
     
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