Block Heater effectiveness 5.7

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Stavinksi

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Temp was 78 this morning and it’s colder than yesterday so plugging warm made a slight difference maybe. Probably not worth the electricity. I will use it a lot more now, had no idea it worked that well. Thought these were diesel things not really effective on gas.
 

canadiankodiak700

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It's good to keep it on all night for keeping the battery and washer fluid reservoir warm. Absolutely not necessary, but it does technically help some. I think the added warmth under the hood helps keep the windshield from frosting over hard as well if it's parked outside.

I like having mine sitting around all warm and toasty under the hood and watching water drip off the hood when it's 20 degrees outside
Plugging in the block heater will do. Absolutely nothing for your battery or your washer fluid. It barely makes a difference with the oil. The coolant does not get up to a high enough temperature to heat the engine bay. It definitely does not prevent your window from frosting over, again. Engine bay does not heat up that much.
 

crash68

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I wish there a "reverse" inverter where the DEF and Diesel tank heaters could be running. For well-digger a$$ cold, I guess the keys could be left in the run position with a heavy duty charger/power supply fon the batteries. I used to have a HD 14vdc power supply when I did sound competitions/showcasing back in the day

Last year had a case of DEF freezing and/or Diesel gelling, I could not go more than 40ft and had to sit with the chugging engine for about 15 min before I could go
Frozen DEF isn't going to cause the engine to chug or not start*
Worse case scenario for frozen DEF is a warning message on the dash for reduced power or no start in X X miles. Your chugging issue was a fuel issue.
Thought these were diesel things not really effective on gas.
Gas engines benefit from them but the temperature needs to be a lot colder than -4°F for a gas engine to warrant actually needing a block heater. Diesels need them in "warmer" temps than gas engines due to the fuel ignition type.
For either engine pre-warming the block is a benefit.
 

Frisk

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I plug in my truck as soon as the temp goes below -15C. I have it on a timer and run it for 2 hours prior to my planned departure time. When I start the truck in coolant temp is usually in the +15 to +17 range. If the temp ar going below -20C I plug in my battery blanket and 2 Amp onboard battery charger. Have tested this down to -35C and it starts fine.
 

PaleFlyer

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I have always plugged in my vehicles at 0 C or 32 F. At that temp the timer is set for 2 hours prior to leaving. at -15 it goes to 3 hours, at -25 5 hours, below -35 it runs all night. The gas jobs, with 0w30 or 0W40 synthetic oil, will start just fine not plugged in, at least to -35 or so, and diesels to about -20 C but they warm up WAY faster and it is a lot easier on the motor. Cold starts account for a great deal of wear on any engine, and the colder the worse it is. Electricity is pretty cheap. Even at -40 outside parking, you will see your coolant have temp in it that is above 32F from the block heater.

I also run an in car warmer so I don't have to scrape windows. Basically I start the truck and drive away gently. Let it warm as I drive.
Links?
 

Ram1958

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Weather getting ugly, supposed to be 4F (-16 C) tonight. My truck has an engine block heater. I plugged it in this evening for the first time ever. It was around 16 degrees F outside when I plugged it in. I understand from the spec it is around 600W. How warm should I expect this to be in the morning? Doesn’t seem like 600W could do much against 4 degree weather to a lump of steel. On the other hand… why do they offer from factory if it doesn’t help?
-41c here last week and never plugged my 20 in. Wind makes no difference on how cold the engine gets. I much prefer to pump cold oil into a cold cylinder rather than cold oil/ warm(dryer) cylinder.
 

turkeybird56

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Difference with a gasser, they doesn't rely on the heat of compression to ignite the fuel/air mixture. The colder it gets the more of a struggle it is for a diesel to light off, with a gasser the fuel/air ratio just needs to be close. Too cold for gasoline is when the temp is closer to -100°.
The block heater will help the engine warm up faster .
IF it gets to - 100F here, I quit !!!!!!!!!. That -5 F in Feb 2021 was cold enuf for this now acclimated Boird, hee hee.
 

turkeybird56

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If it gets to -100°F in Texas, you probably won't have to worry about quitting... Everything would have stopped already...
In Feb 2021, it got down to -5 F in the middle of the state, basically shut down for 5 days.
 

Wild one

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-41c here last week and never plugged my 20 in. Wind makes no difference on how cold the engine gets. I much prefer to pump cold oil into a cold cylinder rather than cold oil/ warm(dryer) cylinder.
Not me,as the oil will warm up that much faster on a warm block.You're not pumping oil into the cylinders anyways,the only oil hitting the cylinders is from the oil flung off the crank,and that's the same oil that lubes the camshaft lobes and lifter rollers,and cold oil doesn't fling off the crank worth crap,so that means your camshaft runs with-out lube that much longer.Personally i think you're nuts not to plug it in at temps below -30C,but that's only my opinion.Put an oil pan heater on it,and you'll have warm oil at start-up
 
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Stavinksi

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-41c here last week and never plugged my 20 in. Wind makes no difference on how cold the engine gets. I much prefer to pump cold oil into a cold cylinder rather than cold oil/ warm(dryer) cylinder.
What do you mean by dryer in parentheses? I’m not sure I follow the logic. YouTube science never lies right? Here are some interesting videos on super cold oil and viscosity.


 

Marshall

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See if you can reroute the plug out one of the tow hooks if you have them, possibly use a short extension cord. I have mine zip-tied to the tow hook and use a smart plug that I can program to turn on a couple hours before I have to leave whenever the temp is below 40°

Update: it only got down to 9F so wasn’t as cold as expected. Started the truck this morning, display said coolant was 73F a few seconds after starting. If did seem to start easily and it for sure had heat quickly. May start using that any time it’s below freezing. It really needs an external plug of some sort. It is cold futzing around with extension cord and that stupid cover under the hood when it’s 9 outside, can’t imagine if it were -9!
I don't know about yours, mine is older, but the block heater cord is zipped tied to the top of the rad support on mine, I just have plug end sticking out top of the head light, if I plug in, not usual as it sits in garage and I am retired .
I think if you cut the zip ties , you can get it out the bumper.
Last week we had -40 , I did plug it in for that. The north pole was warmer.

Back when we where using reg. old " real" oil, a block heater made a hell of a difference. I had oil heater on my tractors.
Syth. make a huge difference these days when real cold.
 
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Wild one

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What do you mean by dryer in parentheses? I’m not sure I follow the logic. YouTube science never lies right? Here are some interesting videos on super cold oil and viscosity.


I like the comment about -40 being a cold day at the north pole,last week Edmonton International Airport was recording -50C/-58F for a couple days,-40 would of been a nice day,lol
Track DA was also -5000ft,man i'd of loved to make a pass at that DA,as our normal summer DA is 4000+ft,so that'd be a good mile and half lower DA
 
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PaleFlyer

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Happy to but to what?
The in-car specifically, here in the piedmont area of NC, we don't often get into the negatives, but it still gets damn chilly sometimes, and the wife doesn't get that a "big" 5.7 (She has a 2.7L 4 banger in her Rav4) doesn't get "warm" just idling for a couple minutes before the boys get loaded. So trying to find things I can retro into the 1500 to help it get to a not-nipple hardening temp without it having to idle in the driveway forever.

And also a way to run said bits and bobs, and not have a flat battery every morning. (Damn truck does that enough on it's own, it doesn't need an assist.)
 

Dean2

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In car warmer. Have used this model for decades. Plugs into the extension cord along with your block heater. You need to run it out through the firewall. The plastic tab is so you can mount the heater to the hump or side panel, you only need clearance for the outlet, the rest is well insulated. You can use a regular electric space heater if you want to try this idea out before buying a dedicated in car warmer.


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The power cord I run through the grommet for the emergency brake. Use an round awl rather than a knife so the hole doesn't spread.

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Inexpensive extension cord holder that can attach to bumper, grill etc so in car warmer and block heater can stay plugged into the extension cord and the cord is handy for plugging in. Also from Canadian Tire, about 8 bucks.


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PaleFlyer

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In car warmer. Have used this model for decades. Plugs into the extension cord along with your block heater. You need to run it out through the firewall. The plastic tab is so you can mount the heater to the hump or side panel, you only need clearance for the outlet, the rest is well insulated. You can use a regular electric space heater if you want to try this idea out before buying a dedicated in car warmer.


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The power cord I run through the grommet for the emergency brake. Use an round awl rather than a knife so the hole doesn't spread.

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Inexpensive extension cord holder that can attach to bumper, grill etc so in car warmer and block heater can stay plugged into the extension cord and the cord is handy for plugging in. Also from Canadian Tire, about 8 bucks.


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Where does the unit itself sit? Like is it just chilling on the dash?

And does it have some form of built in thermal control, or does it just blast 900W of heat at all times? (I'd hope for $200 canunicstan copecs it has built in thermal control...)
 

Dean2

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Where does the unit itself sit? Like is it just chilling on the dash?

And does it have some form of built in thermal control, or does it just blast 900W of heat at all times? (I'd hope for $200 canunicstan copecs it has built in thermal control...)
The plastic tab is screwed to a convenient location and the heater slips onto that. It slips on and off easily so you can remove it if you want for the summer. Most guys screw the plastic holder tab to the center stack, the floor between the front seats if you don't have a full center console or to the passenger side foot-well. It can even be mounted in the back seat if you want. Like I said before, you just need enough clearance for the hot air coming out the front of the unit.

It has overheat protection but it does pump heat the whole time it is plugged in, just like your block heater does. That is why most of us use a timer, and set the run time based on how cold it is. The idea is to mount it close to floor level as heat rises.
 

Marshall

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Back when I used interior heaters, and before the huge center console We would just hang them under the lower dash , mainly for the early morning drive to work ( I did that for a while)
It would keep the window cleared of frost in the mornings. I use to have a real slim one in one of the cars where leg room was not great.
 
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