Car cover during the winter

easysurfer

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In December I might have to leave my car parked outside for about 10 days straight. I'm afraid it'll be cold and my battery would be dead on return.

If I was to get one of those car covers to put over my car, would that help much? Also, if I was to leave it out, would putting something like a throw blanket over the engine help keep it warm?
 
Granted, the type of batteries used in vehicles are harmed slightly by the recharging process but what is the big deal? If the battery is dead, a quick "jump" would take care of it.

Nevertheless, I don't believe that cold, in and of itself, depletes the charge to any significant degree -- an engine is harder to start when very cold, however, and stresses the battery. The main reason a battery losses it's charge -- regardless of temperature -- is the "draw" from the vehicle -- radio/clock, computer, etc. This can best be overcome by simply disconnecting the battery during that period (be prepared to reprogram the radio).
 
That's right. The battery has a constant drain on it from the car's electronics.

Assuming your battery is in good condition (you do have it checked regularly, don't you?), the simplest answer is to keep a pair of jumper cables in the trunk.
 
The car cover will not help. How cold are you talking? More than 20 below when you try to start it?
 
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I don't know how cold...December weather by me varies a lot, it may be 60 degrees or -5 degrees :blush:. (Seriously)

I do practically have new battery and a portable jumper it it won't turn over.

Good idea about perhaps disconnecting the battery.
 
Not so cold. Odds are you will be fine. Disconnecting the battery would stop the draw but 10 days isn't that long of a time. I'd take the risk and do nothing. My car sat nearly three months in the middle of winter last year and started right up in the spring. I was going to put the battery minder on it and forgot before I left. But my car does not have a lot of parasitic load on the battery. No lighted radio, etc.
 
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I store my sports car over the winter months. I've had a new battery go 6 months without needing a jump. Unless you happen to have specific cars with a high drain (BMW, MB, Audi) I wouldn't think twice about 10 days.

A car cover is to protect the paint only. On top of that the car must be spotless before putting it on otherwise it will do more harm than good by scratching the paint.
 
Thanks for the advice. I'm not that worry about the paint. If scratched that will math the rust on the side :LOL:.

I just want it to start up when I return. From the feedback here, looks like 10 days should be too bad, especially with a good battery.
 
As the others have said, should be no problem. If parking at an airport lot - they generally have a jumper handy. Or carry some jumper cables, which are not a bad idea to own anyway.

Some folks use these for batteries that sit for a long time, like generators or bulldozers, etc.:

1.5 Watt Solar Battery Charger
 
Not so cold. Odds are you will be fine. .
Not so cold! Warning. Look at Martha's profile - see where she lives. They don't even put socks on until it's below freezing during the day.:) I know this because I have friends that used to live in Minnesota.

Look, there are three levels of cold:

1. Cold
2. Efing cold
3. Hi there. I'm from Minnesota .. eh:)?

easysurfer, a cover might help if it's very cold and seriously windy and your battery is old. You're probably better off keeping the money and using it to pay a tow truck for a jump start in the unlikely chance you have a problem.
 
As the others have said, should be no problem. If parking at an airport lot - they generally have a jumper handy. Or carry some jumper cables, which are not a bad idea to own anyway.

Some folks use these for batteries that sit for a long time, like generators or bulldozers, etc.:

1.5 Watt Solar Battery Charger


Interesting product. Good thing to keep in mind.
 
I live north of Martha and I go away regularly during the winter. I leave my car (15 year old Honda) in the garage, which keeps it away from the wind, but around here it can get down to minus 40 Centigrade (that's also minus 40 degrees F). When I come back, I plug in the engine block heater for 3-4 hours, and I'm good to go.

Block heater - Wikipedia, the free encyclopedia
 
Not so cold! Warning. Look at Martha's profile - see where she lives. They don't even put socks on until it's below freezing during the day.:) I know this because I have friends that used to live in Minnesota.

Look, there are three levels of cold:

1. Cold
2. Efing cold
3. Hi there. I'm from Minnesota .. eh:)?

easysurfer, a cover might help if it's very cold and seriously windy and your battery is old. You're probably better off keeping the money and using it to pay a tow truck for a jump start in the unlikely chance you have a problem.


Weather is relative. I could walk in a room and go "man it's chilly here, don't you think" then the person there would say, "gosh, I'm sweating" :)

I know that's the same with humidity and heat. There's warmth, then dry heat, and muggy stuffy heat.

Back to my car. At the old place where I lived, there was only a parking space. No indoor garage. I didn't drive every day (commuted by train). The car usually started. But it was also much newer then too.
 
Now I'm curious. Does wind chill factor have any meaning in this context, or are we talking strictly air temperature?
 
I leave a car out for 3 weeks to a month over Christmas and into January every year when I go to FL. Previously I left my car in long-term parking at the airport but I have recently been leaving it with a park and ride near the airport as they will clean the snow off if necessary and also make sure it has started and is warmed up when I return home. I am getting the older car I leave inspected in a week. Maybe I will have them drop in a new battery whether I need it or not. I think I had the battery replaced about 3 years ago but it is cheap insurance.
 
I've always wondered. If a car is covered with snow, would that keep it warm (igloo effect?). As braumeister asked, Is the cold against batteries mostly the wind and wind chill or ambient temp?
 
Now I'm curious. Does wind chill factor have any meaning in this context, or are we talking strictly air temperature?

Wind chill and it's warm weather counterpart, heat index, are measurements of the perceived temperature on human skin and are moisture-related. They aren't meaningful when it comes to a car or a car battery.
 
Wind causes convection, so at a given temperature, wind will cause a warm object to lose heat to the environment more quickly. But after everything has equilibrated, it's just damn cold. :eek:
 
In December I might have to leave my car parked outside for about 10 days straight. I'm afraid it'll be cold and my battery would be dead on return.

If I was to get one of those car covers to put over my car, would that help much? Also, if I was to leave it out, would putting something like a throw blanket over the engine help keep it warm?

There are two problems with the cold. It slows the chemical reaction which is the basis of how your battery works. That cuts the power to turn the starter motor. The cold also thickens your oil which means you need more cranking power to turn over the engine. If anything, the cold actually slows down the very gradual loss of electrical power stored in your battery because it retards the chemical processes that go on even when the battery is not being used.

Unless your car has a significant phantom drain (e.g., clock, anti-theft, etc.) 10 days sitting won't change your battery charge perceptibly. If you want to be certain your battery is okay, take it to your mechanic and let them check it. If it's okay, don't worry about it. If you are a worry wart, spend 1/4 or 1/3 the money of a good car cover and buy a sealed battery jumper instead (Walmart, Sams, etc. - maybe $50 - $60). Throw it in the trunk (after charging). It's good to go for several months before recharging - if you don't have to use it. If your battery ever poops out, you don't need to get a jump from anyone. Just whip out the "jumper" and do it yourself.

Oh, yeah. YMMV.
 
Another thing that helps, at least in ND, is to use synthetic oil. Synthetic does not thicken up at very cold temps, it has to get to about 60 below before that happens. It will help reduce the power needed for the starter to spin the engine.
 
I've always wondered. If a car is covered with snow, would that keep it warm (igloo effect?).
Only if the bottom of the car is also covered with snow, which is typically not the case. Otherwise the cold air is going to be circulating around the engine compartment from below. If you drive round on a cold day with the heating not pointed at the floor, you can probably feel the cold coming right off the floor pan.
 
Some of you are forgetting that he is talking about 10 days in the "cold" (relative term).

After about 1/2 a day, wind chill will have zero effect. The car will be essentially as cold as ambient whether it has a cover, snow or anything around it. It is no longer producing heat - wind chill effect is over and done with. A cover is not a solution in any way (well, maybe keep snow from blowing in the engine compartment and melting and shorting out the spark plug wires - but that's a stretch).

As others have mentioned, current drain can be a problem, regardless of temperature. The solar chargers probably could help, but if I were worried, I'd just throw a cheap battery charger on the car for a few hours after I got home. That should be enough to replenish any charge lost to parasitics.

-ERD50
 
When you park the car before your trip, remember to park it so that you can get to the battery to jump start it if needed (usually, that means backing into the parking space). Also turn off all your accessories (radio, lights, heater/defrost blower, rear window defroster, etc). Although some cars de-activate these as the car is being cranked, you don't want to take the chance--you want all available juice flowing to the starter.

I've got one of those small solar battery trickle-chargers. I don't know if it makes any difference, but I haven't needed a jump start since I got it.

Be sure your car has the right weight oil for the winter. Many new cars recommend 5W-30 year-round now, but some manufacturers recommend thicker oil in the summer, thinner in the winter. If you've got oil that's too thick in the winter the car will be a little harder to start, and it also won't be good for your engine.

No car cover or engine blanket is going to keep your car any warmer for a 10 day period, unless it has a plug on it.

You should be fine. The battery is new, the weather isn't that cold, and 10 days is not an extremely long time.
 
If you're still using analog keys to open the door locks then you might want to squirt a little WD-40 in the keyhole before you leave. It beats the emergency alternative.

Y'all are making me feel a lot better about our last three days of rainy weather and today's 72-degree surfing conditions.
 
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