Dumb Question

[Superglide]

Not that I've ever done it or would dream of doing it but was wondering what damage would occur if you started your truck with the block heater plugged in. Never saw anything in the owner's manual about it.

 

[AH64ID]

Wouldn't hurt a thing, do it all the time.



Just don't drive away with it plugged in, thats where problems occur.

 

[PBJ2500CTD]

Not that I've ever done it or would dream of doing it but was wondering what damage would occur if you started your truck with the block heater plugged in. Never saw anything in the owner's manual about it.

Not a problem - until you drive off... :-laf

 

[AWeiman]

my wife does it all the time as well. plugged in truck and remote start = toasty truck. she only tried to take the extension with her once. :-laf luckly i use a long cord and she stopped before she caused any damage to anything.

p. s. my brother is a diesel mech and told me it should be fine.

 

[Superglide]

Okay then, thanks for the responses.

 

[HHhuntitall]

Yep, should be fine. The block heater is independent from other truck electrical systems. It's basically a heating coil, similar to a water trough heater you'd see around livestock, just a little smaller. It goes into the anitfreeze in the engine block between #3 and #4(I think it is. . ) and heats the water to warm the engine block, pistons, oil... . you get the idea. Size depends on amperage, and most of ours are the smaller versions available, same as used on many over the road trucks in the Southern U. S. I use a 15amp timer and set it to come on 3-4 hours before I plan to start my truck, then it uses less electricity(that's in 0-20* weather). I've also started a truck and plugged it in to help it warm up. You can leave them plugged in all night. Doesn't hurt a thing except the bill at the end of the month!!

 

[tp0d]

The block heater uses approx 750-800 watts in use and will never hurt if you start the engine with it plugged in. Just a dumb heater, nothing more.

I use a timer on mine, about 2hrs in 20F weather, and 3-5hrs in 0F or less weather

-j

 

[Hoefler]

We do it all the time to our fire trucks. Some of our trucks have a automatic ejector, when you crank it over, it shoots the plug out. On others, we have the plug located on the rear of the truck so when you drive off, it pulls out.

 

[timelessconstructionllc]

won't hurt a thing. i did learn the hard way about driving off with it plugged in though. being as how i always back into my driveway i decided the plug in the front wasn't the best idea so i got a 25' extension cord and ziptied the female end of the ext cord right next to the male end of the oem block heater cord (next to my tow hook) then i ran the extension cord down the frame and the male end comes out right next to my license plate that way i can just leave the original cord plugged into the ext cord in the front most of the time and then i just plug in at the back so if i drive off it just pulls itself loose for me without ripping the cord in half. and if i want to plug in in the front then i just unplug the cord that runs to the back and plug in there.

 

[Mark31]

I figured out it is wise for me to leave a reminder on the dash when I plug 'er up. That is a heap less trouble than having to fix a mess! No, I havn't driven off pluigged up, but I did start up once!

 

[Superglide]

Thanks again for the replies. I don't plug it in at home (Vancouver area) but I do when I'm up at the lake. Temps there a few weeks ago were -29F. The use of a timer is a great idea as well.

 

[04blackcherry]

It's not a dumb question... I was just afraid to ask.

 

[AH64ID]

The use of a timer is a great idea as well.

It's quite worth it. Dodge says it take a min of 1 hour to get a benefit from it. I have found thru experimenting that 90 minutes gets you to 90% of the overnight temp at a fraction of the cost. Unless I am on a hotel's dime I don't bother plugging in overnight, no real benefit from the cost.

 

[Wertles]

I plug it into the truck then run the cord over the drivers side mirror. Haven't forgot to unplug since.

 

[RLHannink]

I'd heard that the element can get damaged by cavitation from the water pump, I always have unplugged first. But, after reading this, maybe it doesn't matter.



The habit of unplugging first has a benefit that you'll never drive off with the cord

 

[Prairie Dog]

I'd heard that the element can get damaged by cavitation from the water pump, I always have unplugged first. But, after reading this, maybe it doesn't matter.



The habit of unplugging first has a benefit that you'll never drive off with the cord

True. Don't know if it's cavitation or just the water pump moving a large amount of cold water to it but my mechanic friend, who has replaced them on all sorts of rigs, tells me the only time he has had to replace them is when the operator leaves it on and starts the truck. Indeed I replaced one on a friends Dodge that ran it while running his truck. Obviously peoples luck varies.

So to be safe, I don't do it.

 

[rbattelle]

The habit of unplugging first has a benefit that you'll never drive off with the cord

my mechanic friend, who has replaced them on all sorts of rigs, tells me the only time he has had to replace them is when the operator leaves it on and starts the truck.

I'll tend to agree with everyone else that it doesn't really matter. Nevertheless, I always unplug it before starting. I notice the owners manual says not to run the truck with the heater plugged in. Maybe this cavitation issue is why?



-Ryan

 

[HHhuntitall]

I don't know how cavitation would affect it while it's plugged in and not when it's unplugged. It's a round, metal, tube with a heating coil inside it. It might cause the engine to run excessively hot at an idle, if you left it plugged in for hours at a time..... but there's no point for that. I don't see a point in leaving it plugged in for any longer than it needs, but I don't see how it can be hurt either way. Pointless argument, I guess, but I'm just looking at it from a mechanical standpoint. I've put in several myself. Firsthand knowledge. I have two, a used one and a new one in the box in my shop in a filing cabinet I keep Cummins Engine parts in. I'll tell you the average man can't bend one with his bare hands, so I see no way cavitation could hurt it.

 

[DGamelin]

I have ran mine with it on but I try not to, I dont use it much. It is the air bubbles or air pockets that manufacturers are worried about. They need water to cool themselves. I have seen block heaters burn the element in two. The small engines more often, like tractors that will boil the water out of the engine.



_________________________

93 250 2wd xc 354 auto 281k

04. 5 3500 4wd qc dully 373 6speed 119k

 

[AH64ID]

If you have enough air bubbles to damage a block heater in a minute or less of operation then you probably have other issues as well.