Cold Car Starting / Driving

[Crocuta]

Plug it in at night and it keeps your oil nice and viscous. 

Why would you want your oil viscous?

Because I need to stop posting late at night when my little eyes are tired and my brain makes funny noises.

You know what I meant.   

[Kat Kanning]

Oh, I thought maybe I was missing something about the way cars run 

[Caleb]

The only good reason to let a modern car "warm up" is so that it isn't below zero while you're sitting in it!

Exactly!  Who cares about the engine?  I don't want to be sitting in 5 degree temperature. 

[mvpel]

Ford/Mercury luxury cars used to, and may still, have an option for a windshield de-icer.  It was a very big current draw, so you needed a heavy-duty battery to go with it. It was first offered in 1989 and used diffused metal particles in the plastic layer of the safety glass, and by passing electric current through them it heated the windshield.  You could tell by the bronze tint of the windshield.

The insurance companies didn't like it much, though, since the windshield cost about two grand to replace.

I guess the trend these days is to heat the wiper fluid instead.

[aworldnervelink]

And, as a point of interest, EZPass will not work with such windshields:

http://www.ezpass.com/static/info/exteriortags.shtml

[maineiac]

They added heaters to the SRB joints, as I recall.  Rube Goldberg would have been proud.

I decided to go ahead and get an engine block heater for our Acura TL, since we tend to use it for rather short trips during the week.  It replaces the lower drain plug for the engine coolant, and has a heating element that you plug into a household outlet which during very cold weather gets the coolant up to about 50 degrees in three hours or so.  This, of course, results in a much quicker warm up, and better engine efficiency - they say up to 20% mileage improvement for short trips.

They're much more common further north, but for our driving patterns and typical New Hampshire winters, I figured it was worth doing.

Growing up in "The County," (that's ov-ah he-ah--actually, up thay-ah) most people had block heaters just so they could start their cars in the morning, period, nevermind efficiency. Even "up thay-ah" though, winters aren't what they were in the 60's and 70's.

I don't even think winter down he-ah has been cold enough to sustain a thread like this, but someone up in Dixville Notch may see it differently!

I say, if you can see well enough, go! She'll wahm up a lot fas-tah, too!

[eques]

I got into my car this afternoon and thought, "gee, balmy!"

I drive by the bank and it's 15F.  That would be considered rather cold in NJ.

I like the cold.   :eastsnow:

(At least, I'd rather be too cold than too hot!)

[MaineShark]

Hey you live in Maine...

I live in NH

...you know that when you start talking below zero materials start behaving differently than at there operating temperature. Tolerances change, everything groans like hey I don't want to move.

Yeah?  And?  If the oil is matched to the temperature, it will be plenty thin enough to drive.  And the engine warms up much faster while under load than idling, so the amount of wear is actually reduced.  That doesn't mean to go out and drag race on a cold engine.  But normal driving will warm the engine faster and actually reduce wear.

The space shuttles O rings failed to seal at just below freezing. I bet they wished they could have let it warm up a little before take off.

That was a design flaw.  They should have sealed correctly, except the design didn't account for the temperature fluctuations.

Weren't the O rings used on the liquid fuel tanks (which, at STP, is in a gaseous state, implies that it is very cold in a liquid state)?

No, the o-rings in question seal the joints between the sections that make up the solid rocket boosters.

Joe

[Tom Sawyer]

Hey it's your car drive it the way you want.

I don't even like to start my car if it gets below zero... I will if I have to.

It's just hard on stuff to put a load on it until is has warmed up some. Driving gently is probably not too bad. But I have a test for you... park your car at the bottom of a steep hill and when it's 10 or 20 below start it and charge up the grade. You'll hear a hell of a rod knock.

Besides my own experience I follow the advice of mechanics with 40+ years of experience. At my buddies shop we used to see a large number of failures when the weather first got real cold or hot.

[MaineShark]

It's just hard on stuff to put a load on it until is has warmed up some. Driving gently is probably not too bad. But I have a test for you... park your car at the bottom of a steep hill and when it's 10 or 20 below start it and charge up the grade. You'll hear a hell of a rod knock.

I've never heard any of the vehicles I own knock at any time.

Besides my own experience I follow the advice of mechanics with 40+ years of experience. At my buddies shop we used to see a large number of failures when the weather first got real cold or hot.

I'd suggest talking to an automotive engineer.  Or any competent mechanical engineer.  He might know a bit more about materials science and fluid mechanics...

Remember, most people don't use the correct oil for conditions.  Most people don't think anything other than 10W30 and 10W40 exist (or, don't know why the other weights exist, if they are aware of them).  Your owner's manual should tell you what oil weight to use for different temperature ranges.  Most likely, you'll be advised to drop to 5W30 in colder weather.

No matter what you do, starting an engine when it's cold out will increase wear.  Idling it to warm up, then driving it causes greater wear than driving it gently until it is warm.  Not to mention wasting gas, which ain't precisely cheap these days.

Joe

[Russell Kanning]

I've never heard any of the vehicles I own knock at any time.

Joe! Turn down the radio!

[MaineShark]

I've never heard any of the vehicles I own knock at any time.

Joe! Turn down the radio!

Heh.  I'm one of those freaks who actually drives with the radio off much of the time.  I like listening to a happy engine running up and down through its load range

Joe