block heater

[Mace Canute]

brokenot, I don't think anyone will ever convince them otherwise, at least not with the use of logic, physics, and empirical evidence. Excellent try though! This reminds me of the "Will this plane take off?" thread, where so many swore up and down that it couldn't possibly fly.

 

[Don87]

brokenot, I don't think anyone will ever convince them otherwise, at least not with the use of logic, physics, and empirical evidence. Excellent try though! This reminds me of the "Will this plane take off?" thread, where so many swore up and down that it couldn't possibly fly.

You can't convince us otherwise because we have been in the 'actual working conditions' where it has happened.

All of your 'logic' your 'charts' your 'graphs' and your 'physics' have utterly failed to show why these conditions exist, or why these conditions have the ability to do the things you say they cannot.

We have actual experiences
of this happening, but some of you try to tell us that it isn't..........wheres the lack of logic?

 

[Mace Canute]

You can't convince us otherwise because we have been in the 'actual working conditions' where it has happened.

I'm 59, grew up on a mixed cattle/grain farm and have worked out on my own for over 40 years. The overwhelming majority of those 40 years involved working outdoor as a Lineman for the power company, doing construction and maintenance. I've ran many tractors, trucks, and assorted equipment in Saskatchewan, B.C, and The Yukon and have worked in minus 65 degree windchill conditions and minus 40 degree calm conditions.

I think that qualifies as "actual working conditions".

All of your 'logic' your 'charts' your 'graphs' and your 'physics' have utterly failed to show why these conditions exist, or why these conditions have the ability to do the things you say they cannot.

If a person won't believe in logic, physics, and empirical evidence, the only alternative is believing in magic.

I refuse to believe in magic.

We have actual experiences
of this happening, but some of you try to tell us that it isn't..........wheres the lack of logic?

Some people tell us they have actual experiences of being abducted by aliens...and probed! Doesn't make it true.

 

[Don87]

I'm 59, grew up on a mixed cattle/grain farm and have worked out on my own for over 40 years. The overwhelming majority of those 40 years involved working outdoor as a Lineman for the power company, doing construction and maintenance. I've ran many tractors, trucks, and assorted equipment in Saskatchewan, B.C, and The Yukon and have worked in minus 65 degree windchill conditions and minus 40 degree calm conditions.

I think that qualifies as "actual working conditions".

If a person won't believe in logic, physics, and empirical evidence, the only alternative is believing in magic.

I refuse to believe in magic.

Some people tell us they have actual experiences of being abducted by aliens...and probed! Doesn't make it true.

I also have the 'actual working conditions' I was a mechanic for quite a few years.

I can't count the number of tractor trailers that I had to do road service on because they were froze up and they were driving down the highway when it happened. Was running fine when they left the truck stop at Keysers Ridge, Md., but it froze up while moving.......you have yet to explain it.

But let me assure you, only 'wind chill' is going to cause that.

As I stated earlier, I can park my tractor trailer.......nose into the wind.........and at 10 below zero with 30 mph winds, it won't start.
Park the truck with the nose away from the wind and it does start in the exact same conditions.

As of yet, you have failed to explain why this happens.

But i'll tell you again.......the only difference between the 2 scenarios, was the wind angle.

Same truck, same fuel, same location, same ambient temperature.

 

[irvingj]

Wow, this is getting pretty heavy... but I'll stick my neck out anyway....

My take is that there's less residual heat when there's a breeze.... and my suspicion is that if all internal metal parts' temps could be measured, you'd find colder "stuff" after sitting in a cold breeze than in calm air, only because there had been more heat removed; that there is, even after sitting many hours, still some residual heat left, unless convection losses have been increased by air velocity.

In other words, even if parts won't get any colder than ambient temps (and I agree, they can't), stuff will cool off more/faster in a breeze than in still air. I think that's what one poster was referring to when he mentioned cold being "driven deeper."

Either that, or it's magic!

In any case, I run my block heater for about a half hour, unless it's below zero-- then for almost an hour. Just enough to help the lil' diesel start.

Mace-- good explanation; I didn't know just what the flash point of diesel was, but did understand that compression of air will only raise air temps a certain number of degrees-- if the rise ends up below the flash point, yer outta luck.

Question that perhaps you could answer, Mace: is my understanding correct that, for a given compression ratio, a graph of temperature rise vs. ambient air temp would be non-linear? I really don't know, but suspect that's the case. (I'm not being smart here-- really want to know, and you sound like you know more about it than me!)

 

[flyingcow]

Don87
generally the trailer trucks that left the truck stop and froze up, got bad fuel or had sh!tty fule filters that needed to be changed. Didn't need much fuel to sit at an idle, but put 'er into the wind, now you need a lot of fuel. Restriction of some kind happened. And i'm sure the highway speed didn't help.

Give me two identical units(not plugged in to a block heater), park one into the wind at zero, park the other sheltered from the wind. The one parked into the wind will start harder. Switch units from night to night. The one that's not sheltered, will start harder. Will it start? Most of time it should, but there will be a noticeable difference in how it does, and make a difference in how quick it comes up to temp. Just know what i know.

 

[Don87]

Don87
generally the trailer trucks that left the truck stop and froze up, got bad fuel or had sh!tty fule filters that needed to be changed. Didn't need much fuel to sit at an idle, but put 'er into the wind, now you need a lot of fuel. Restriction of some kind happened. And i'm sure the highway speed didn't help.

Give me two identical units(not plugged in to a block heater), park one into the wind at zero, park the other sheltered from the wind. The one parked into the wind will start harder. Switch units from night to night. The one that's not sheltered, will start harder. Will it start? Most of time it should, but there will be a noticeable difference in how it does, and make a difference in how quick it comes up to temp. Just know what i know.

That was the point I was making, the fuel filters were fine(cause I had just changed them), it was the wind chill, from driving down the highway that caused the fuel to gel.

Most trucks nowadays have antifreeze piped through the fuel tanks to keep the fuel warm.

 

[Ford tractor]

I also have the 'actual working conditions' I was a mechanic for quite a few years.

I can't count the number of tractor trailers that I had to do road service on because they were froze up and they were driving down the highway when it happened. Was running fine when they left the truck stop at Keysers Ridge, Md., but it froze up while moving.......you have yet to explain it.

But let me assure you, only 'wind chill' is going to cause that.
.

I'll stick my neck out and give an explanation a shot.

Trucker fills up in Central Illinois at 50F and heads north into a cold front in northern Wisconsin where it's -30F. The fuel from Ill is treated to 0F and as soon as he gets far enough to where the fuel starts to cloud -- his miles are numbered! Soon the filter is packed and he is parked.

I've had that scenario strike in the fall when an early cold snap strikes and the fuel stop's all have basically untreated fuel.

 

[Mace Canute]

Question that perhaps you could answer, Mace: is my understanding correct that, for a given compression ratio, a graph of temperature rise vs. ambient air temp would be non-linear? I really don't know, but suspect that's the case. (I'm not being smart here-- really want to know, and you sound like you know more about it than me!)

It's covered by Charles Law.

"At constant pressure, the volume of a given mass of an ideal gas increases or decreases by the same factor as its temperature on the absolute temperature scale."

The corollaries hold true also. Decreasing the volume increases the pressure and the temperature rises. For practical purposes it's linear.

If you scroll down to Figure 9.4 here, it shows a couple of graphs and explains why the Kelvin temp scale is preferred.

 

[Reverend Blair]

At what temperatures does "moisture" constitute something other than snow? If we're discussing ambient temperatures at which any moisture blowing around isn't already "frozen", then the tractor or vehicle not starting has other issues because it's not cold enough outside for it to not start because of the cold.

The amount of moisture air will hold changes with the temperature. That's why it rarely snows when it's minus 30. So if you park into a slight breeze when it's -10 and the temperature drops as the wind comes up, the air will deposit moisture. That's physics too, btw. There's more than one equation.

Blocked airways are another discussion entirely. A blocked airway has nothing to do with ambient temperature. We're talking about the alleged "wind chill" effect here.

No, we're discussing whether vehicles start harder when parked into the wind. Nobody is doubting the physics. And yes, blocked airways have everything to do with ambient temperature in some circumstances...such as when you park into the wind in the winter. An air-breather packed with snow doesn't let much air in.

I live in a cold place as well. And my particular situation has an added bonus: The people that call me to get stuff going early in the morning are rental customers that aren't familiar in many cases of the proper procedures with a given piece of machinery. If you're familiar with the drill, (so to speak), involved with getting your tractor started when it's cold....you'll be successful in that endeavor usually. Hand someone else the keys and tell them to try their luck without some step-by-step instructions and see what happens. What happens next, is that after they've been unsuccessful after multiple attempts, then you still need to get it going. But the battery is now nearly dead, the starter has had a couple of years' worth of its useful life depleted, the engine may be flooded, etc.

Ah, so obviously those of us who start the same vehicles day after day but have noticed that they start harder when parked into the wind are just too stupid to follow the proper procedure?

We've already agreed on that. Wind will make it cool down quicker, but under no circumstances will it get colder that the ambient temp because of the wind. And that is what "wind chill" is, and why it's referred to as a "factor". It's not "actual". Never has been, never will be.

If it starts *like this* at 10F, then it will also start *like this* at 10F and with a 20 mph wind blowing assuming that in both cases the machinery has sat long enough to cool down to whatever the ambient temperature is.

So you agree that any residual warmth will be gone, that the block heater won't work as efficiently, and that when it first fires it won't necessarily generate enough warmth quickly enough for it to run easily. In other words if you park into the wind it will start harder.

If it starts like this at -30 with no wind, it won't start as well at -30 when parked into the wind.

Anything else is just your imagination at work.

No, thinking that there's only one applicable equation in physics for what is a relatively complex situation is just your imagination.