Block heater left on all weekend :/

[fnlyfnd]

Friday night I pluged in my wonderful block heater, and forgot about it. I didn't leave the house all weekend, since I was trying to get over this cold. This morning I came out to realize what I did. My questions is, could I have done any damage to anything?

[tunered]

if the cooling system was full you did no harm.

[Jerry DeMoss]

Was it cold all weekend?If it was cold then I don't think you hurt a thing.I used to leave mine plugged in all the time when in Alaska because it was -20deg quite a bit.

[Legacy777]

You didn't hurt anything.

[OB99W]

Friday night I pluged in my wonderful block heater, and forgot about it. [...] My questions is, could I have done any damage to anything?

The average (day/night) temp in central NY for the last two days has been around 25 degrees F. I doubt if your block heater got the engine past normal operating temp, even if left on for a couple of days straight, unless it's grossly oversized. The thing you may have hurt slightly is your wallet, to pay for a few kilowatthours of power.

 

You might consider getting a timer to plug the heater into. The 24-hour type would probably do, but the ones programmable by the week allow you to have a different schedule for certain days, like the weekend. Just make sure that the timer contacts are rated to handle the current your block heater draws.

 

--OB99W

[fnlyfnd]

sweet, thanks guys. I'll prolly get a timer tonight when I get out of work. Anyone know how much power this thing pulls.

[Snowman]

For some reason, 1500 watts sticks in my mind, so about 13-15 amps. Most of the timers I've seen are rated for at least 20 amps.

 

And no, you didn't hurt anything. At worst, you wore out the heater unit a little bit. Since I plug my car into the university's outlet, I leave it plugged in for a week at a time and have noticed no ill effects.

[zyewdall]

For some reason, 1500 watts sticks in my mind, so about 13-15 amps. Most of the timers I've seen are rated for at least 20 amps.

 

And no, you didn't hurt anything. At worst, you wore out the heater unit a little bit. Since I plug my car into the university's outlet, I leave it plugged in for a week at a time and have noticed no ill effects.

 

I think they're much less than that. The one on my diesel truck (2.3 liter engine) only draws about 4 amps, or 480 watts. I've never had one on a subaru, but I'd suspect they'd be the same size or smaller.

[Handtool]

You might consider getting a timer to plug the heater into.

--OB99W

 

I'm considering putting in a block heater. How fast do they "work"? How long before you start the vehichle do you have the timer turn the block heater on?

[zyewdall]

I'm considering putting in a block heater. How fast do they "work"? How long before you start the vehichle do you have the timer turn the block heater on?

 

Not sure. 3 or 4 hours depending on temperature and when it was last run I'd think? I've actually never used the one on my truck (although I should have last night -- had to use ether to get it to fire this morning, 7 degrees and 40mph wind last night). Most people just plug em in over night, but maybe you could save power if you knew exactly when to turn it on instead of leaving it on all night.

 

Another option is a battery heater -- a sort of plastic pad that wraps around the battery and keeps it warm so it can crank the cold engine. Alot easier to install, but doesn't do as much as a real block heater.

[Gnuman]

OK, folks. First things first: A block heater is not to warm your block up to temp. It will not do that, and is not designed to. What it does do is keep the coolant in the block from freezing in nasty cold weather. It is insurance against Mother Natures wrath, nothing more. It will keep the temp above the freezing point of the coolant, and the oil. This ensures that those two vital fluids will flow when you start the engine, the operation of the engine will then bring it up to temp. Even if you use it in a warm environment, it will not get to operating temp, unless (as mentioned above) it is badly overpower for the engine it is going into (say, perhaps one for a tractor trailer going into a normal V8. I don't even think it would fit on a Subie). If you are using the OEM heater, you are perfectly safe leaving it on for months at a time, if that is your desire. Me, I could not do that. I cannot stand to be away from my Subie that long

 

What you will get if you use a block heater, that may look like the engine is being preheated, is that your warm up time will be a bit shorter, as the temp does not have as far to climb as it would in an unheated block.

[zyewdall]

OK, folks. First things first: A block heater is not to warm your block up to temp. It will not do that, and is not designed to. What it does do is keep the coolant in the block from freezing in nasty cold weather. It is insurance against Mother Natures wrath, nothing more. It will keep the temp above the freezing point of the coolant, and the oil. This ensures that those two vital fluids will flow when you start the engine, the operation of the engine will then bring it up to temp. Even if you use it in a warm environment, it will not get to operating temp, unless (as mentioned above) it is badly overpower for the engine it is going into (say, perhaps one for a tractor trailer going into a normal V8. I don't even think it would fit on a Subie). If you are using the OEM heater, you are perfectly safe leaving it on for months at a time, if that is your desire. Me, I could not do that. I cannot stand to be away from my Subie that long

 

What you will get if you use a block heater, that may look like the engine is being preheated, is that your warm up time will be a bit shorter, as the temp does not have as far to climb as it would in an unheated block.

 

It won't heat it up to operating temp, but I thought the main idea was to make it warm enough to start when it might not start otherwise (like keeping it 20 degrees instead of -20 degrees), even if it was not actually cold enough to freeze the block -- more a starting aid than a preventing-engine-destruction device. Not that preventing engine destruction isn't good, but it has to get awfully cold before antifreeze freezes, compared to how cold it has to get to make it difficult to start.

 

You can actually get heaters that do bring the engine up to operating temp before starting it. They run on diesel fuel, and cost about $1200, and include auxiliary pumps for the coolant and such. I guess school busses and such run them sometimes. That's a whole nother animal though. I'll defer to the alaskans and north dakotans, who actually use these more than us southerners in CO and NY.

[fnlyfnd]

Good to know. I didn't know hot hot these got. I do notice really short warm up times - like a minute, when I use it. I had one one my old gtp but I didn't drive that in the winter, so I am using this as much as possibile. Yea, its a oem heater, thinking about getting a battery blanket, but in actuallity I should just get a better battery - more cca.

[Tiny Clark]

The idea is to get the engine a bit warm to heat the oil up a bit, so the summamabich will crank. it doesn't take much. The Japanese use to have heaters right on their oil pans, don't know what they do now.

 

You did damage one thing, yer wallet when you have to pay your frikkin' electric bill!

[mtsmiths]

Ahhhh, the joys of a radiant floor heated garage ... both for our 'Roo, and my tender butt.

[Legacy777]

Just something I want to bring up.

 

These cars have fuel injection....if everything is working properly, they will start! The controls, sensors, etc are there to account for the lower temps and the addition of extra fuel.

 

In very cold temps, they should still start. However in very cold temps where you start running into issues is with the fluids. If you have a proper anti-freeze/water mix, you're safe down to like -50 deg or something crazy....so that's not really an issue in my mind.

 

The oil however will start to thicken up. It shouldn't keep the car from starting, however it can making cranking more difficult, and can hinder lubrication at startup. Synthetic oils do not thicken up as much, and are better for extreme cold temps.

 

The block heater is going to help keep the fluids in the engine warmer then the outside. I question how effective it's going to be on the oil in the oil pan to help cold start and thick oil viscosity.

 

Lastly is the battery, battery performance does decrease when temperature drops, and that in combination with the thicker oil (harder to turn the engine), etc may keep the car from starting properly.

 

I think the big things you should do if you live in really cold climates is get a battery warmer, block heater isn't a bad idea, however I'm not 100% sold on their effectiveness alone. But a block heater and an oil pan warmer would definitely be beneficial. Finally, run synthetic fluids.

[zyewdall]

Legacy777 has a good point. Modern fuel injected cars that are running properly will usually not have trouble starting at low temps, unless the combination of cold battery and thick oil keeps it from turning over fast enough. I was thinking more of old carbureated cars and diesels which just won't fire if the carbureator or ignition chamers are too cold. I run synthetic in the winter to allow it to still turn over, and my subaru has started in subzero just fine. The diesel truck turns over fine, but has no motivation to actually fire, which is what warming the block could help with.

 

Just something I want to bring up.

 

These cars have fuel injection....if everything is working properly, they will start! The controls, sensors, etc are there to account for the lower temps and the addition of extra fuel.

 

In very cold temps, they should still start. However in very cold temps where you start running into issues is with the fluids. If you have a proper anti-freeze/water mix, you're safe down to like -50 deg or something crazy....so that's not really an issue in my mind.

 

The oil however will start to thicken up. It shouldn't keep the car from starting, however it can making cranking more difficult, and can hinder lubrication at startup. Synthetic oils do not thicken up as much, and are better for extreme cold temps.

 

The block heater is going to help keep the fluids in the engine warmer then the outside. I question how effective it's going to be on the oil in the oil pan to help cold start and thick oil viscosity.

 

Lastly is the battery, battery performance does decrease when temperature drops, and that in combination with the thicker oil (harder to turn the engine), etc may keep the car from starting properly.

 

I think the big things you should do if you live in really cold climates is get a battery warmer, block heater isn't a bad idea, however I'm not 100% sold on their effectiveness alone. But a block heater and an oil pan warmer would definitely be beneficial. Finally, run synthetic fluids.

[Hondasucks]

I don't know what a subaru one draws, the one in my truck draws 1800 watts! The owners manual says it's recommended below 40 degrees, and required below 0, although I have managed to start the truck below zero before, takes a few cycles of the manifold grid heater though.

 

And as for fuel inj. vs. carb on cold starts, one year it was really cold up in Centennial, which is about 30 miles from here, and my instructor had two fuel injected vehicles (A GMC Suburban and an Escort) and neither one would start, but his wifes 72 Suburban fired right up)

[zyewdall]

Well, you've got a 5.9 liter diesel, vs my 2.3 liter diesel, and the 1.8 in a subaru. So I suspect the subaru one draws less.... Perhaps someone with the factory subaru block heater should just measure it and stop the arguing

 

And now that you mention it, my '82 subaru that wouldn't idle because the carb was so bad, still started up fine in cold weather.... Hmmm....... I retract my statement that fuel injected vehicals categorically start better in cold weather.

 

I don't know what a subaru one draws, the one in my truck draws 1800 watts! The owners manual says it's recommended below 40 degrees, and required below 0, although I have managed to start the truck below zero before, takes a few cycles of the manifold grid heater though.

 

And as for fuel inj. vs. carb on cold starts, one year it was really cold up in Centennial, which is about 30 miles from here, and my instructor had two fuel injected vehicles (A GMC Suburban and an Escort) and neither one would start, but his wifes 72 Suburban fired right up)

[frag]

Yes, electronic ignition is way better than the old carbs and disties.

It's often very very cold here in Montreal between december and the end of february. The Loyale and the Legacy have always started.

What's interesting is that when it's really cold, -20 to -35° C., the engine turns over slower but catches after exactly the same number of revs than when its milder outside (about 4 IIRC).

[vic/se]

I think they're much less than that. The one on my diesel truck (2.3 liter engine) only draws about 4 amps, or 480 watts. I've never had one on a subaru, but I'd suspect they'd be the same size or smaller.

 

 

I bought one at subaru, not expensive tough, and I think it's rated at 400-450 watts

[OB99W]

I bought one at subaru, not expensive tough, and I think it's rated at 400-450 watts

From http://www.allsubaru.com/faq.html

"The heater uses standard 115 volts of power and draws 400 watts."

So, that's at least the case for the one used with recent models.

 

--OB99W