Have you ever tried to start your genny in -40? It aint pretty. Maybe a job for the wife. 
Engine Block Heater Wattage
Laughing Gas
Joined: Jun 2005
Posts: 1,009
Likes: 1
From: Colorado
Also your CCA rating I believe is at 32F battery capacity drops a lot with lower temps. Consider plug in battery wraps then you fool your batteries into thinking and performing like its summer. Full Synthetic oil is a must for you in that condition. also I would change tranny to full synthetic fluid too. WHY? synthetics maintain their stated viscosity across a much wider temp range than dinosaur oils which are probably like grease at that temp.
also you can get diesel fuel heaters too
also you can get diesel fuel heaters too
Senior User
Joined: Apr 2006
Posts: 143
Likes: 0
This is very interesting. Is there any way to heat up a truck with JUST the trucks own batteries? I have 3 in my cummins and it starts on the first crank, even at 0F but I can't help but think it is doing something bad to it being that cold.. I would think with 3 batteries I could run SOMETHING to give it a 1 hour preheat without killing its ability to start.. So anyone got any ideas? I don't have anywhere to plug the damn thing in.. Now, there is a plan B I was thinking about.. I have read about those espars or webasto heaters but being the $$ they are, that is out of the question.. But if I could make my own somehow, I have many 55 gallon drums with WMO I could burn all night to heat my truck, I have nothing else to do with that stuff. But not sure how to build one and everything.
Smokin
Joined: Jun 2006
Posts: 8,849
Likes: 0
This is very interesting. Is there any way to heat up a truck with JUST the trucks own batteries? I have 3 in my cummins and it starts on the first crank, even at 0F but I can't help but think it is doing something bad to it being that cold.. I would think with 3 batteries I could run SOMETHING to give it a 1 hour preheat without killing its ability to start.. So anyone got any ideas? I don't have anywhere to plug the damn thing in.. Now, there is a plan B I was thinking about.. I have read about those espars or webasto heaters but being the $$ they are, that is out of the question.. But if I could make my own somehow, I have many 55 gallon drums with WMO I could burn all night to heat my truck, I have nothing else to do with that stuff. But not sure how to build one and everything.
Is it a Powerstroke you want to preheat or a Cummins?
The block heaters in our trucks pull about as much energy as a toaster. Are you asking about using a battery to run the block heater? Somehow I think no matter how to try and rig that one up you'll end up with either 1) a fire or electrical short or 2) severely dead batteries.
I would just make sure your starting system is as healthy as possible, and let you truck warm up before you take off anywhere, make sure you put some anti-gel in your fuel and your truck will be fine. It doesn't harm it to start cold. Maybe invest in some new batteries, heavy duty glow plug relay, make sure your glow plugs/battery cables are good.
Senior User
Joined: Apr 2006
Posts: 143
Likes: 0
Its the cummins, my ford is at the folk's house, I can't afford 10-12mpg anymore. I don't need to touch anything on the cummins, starts fine in the cold I was just worried about "cold starting" it all the time. Hmm, so if that won't work, crap! Hmmmm, I can't think of anything now. I guess I'll just keep letting it warm up then.
Smokin
Joined: Jun 2006
Posts: 8,849
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Its the cummins, my ford is at the folk's house, I can't afford 10-12mpg anymore. I don't need to touch anything on the cummins, starts fine in the cold I was just worried about "cold starting" it all the time. Hmm, so if that won't work, crap! Hmmmm, I can't think of anything now. I guess I'll just keep letting it warm up then.
It won't hurt your Cummins to start cold...the worst thing you can possibly do is wear out a pair of batteries a bit faster than you normally would. But you can treat your fuel so it does not gel and your truck will start on it a bit easier...
This stuff, if you aren't already using it.
Also diesels do prefer synthetic oil, like Rotella 5W-40, for colder temperatures. The truck will start on it a bit better, it will stay thinner in the colder temperatures than traditional dino.
Also - your powerstroke should get much better mileage than 10-12 mpg...perhaps we can help you troubleshoot that one as well.
Lead Driver
Joined: Jan 2007
Posts: 6,708
Likes: 5
From: Kiowa CO
At -40 it's almost time for a sweater. I personally wouldn't be as worried about the block heater as much as the fuel gellin up in the tank/lines. You shouldn't have to plug the truck in for 2hrs to get it warm enough to start, those heaters warm things up pretty quick, although I have not experimented at that cold of temps. I am willing to bet that plugging it in for even 1/2 to 1 hour will warm it up enough to start just fine. Try it at a 1/2 hour, and if no go, give it a little longer until it cranks over fine.
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Senior User
Joined: Apr 2006
Posts: 143
Likes: 0
My truck is not a powerstroke, it is a worn out 7.3 IDI.. Has an automatic that slips pretty good, thats why it gets 10-12.. Plus I doubt anything you do to it will be able to touch the dodges 26mpg. I use amsoil, I use that diesel kleen, I told you it starts on the first crank, I don't even wait for the light, now if it got in the negatives I might, but I haven't used it yet.. Ford is finally starting good now that I got the manual GP button put in, but still takes some cranking..
Ponyboychris--I agree, my ford will get nice and warm after a night but the dodges doesn't seem to do much of anything.. But if I plug the ford in all night it starts up better than a gasser!
Ponyboychris--I agree, my ford will get nice and warm after a night but the dodges doesn't seem to do much of anything.. But if I plug the ford in all night it starts up better than a gasser!
Smokin
Joined: Jun 2006
Posts: 8,849
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Apparently I read that wrong at some point...
Lead Driver
Joined: Jan 2006
Posts: 6,267
Likes: 5
you can get 12v diesel heaters, that heat the coolant and circulate it , off the batteries.
These suckers warm the block better than the electric block heater.
They are IIRC made for tractors, in case your tractor needs to be left in a remote location over night in a cold place.
These suckers warm the block better than the electric block heater.
They are IIRC made for tractors, in case your tractor needs to be left in a remote location over night in a cold place.
Post Fiend
Joined: Feb 2007
Posts: 14,541
Likes: 2
From: Dallas-Ft. Worth
I guess my question would be why he came to a 99-03 PowerStroke forum to ask a question about his CTD... 
Now, you have been provided several solutions, all of which are good. Personally, I'd use about all of them. I heard that there is a 0W-30 for diesels that would be good if it's that cold -- you might investigate that as well. Use that genny if it's -40 for the block heater. Don't know about the CTD, but one of our members here starts his truck up in NH at -20 with no problems without a block heater. Now at -40, you might need some help, thus the genny idea. I wouldn't think it gets that cold that often. Of course, you might go ask in a CTD forum. They'll probably know the specific issues/limitations with that engine.
I just did a little Googling -- check this one out:
https://lubricationspecialist.com/fr...aspx?fileid=67
Pump runs off the battery, but it uses fuel for heating. That makes it much easier on your batteries. That's important because at -40, there won't be a lot left after running a 1000W heater for 2 hours...
Now, you have been provided several solutions, all of which are good. Personally, I'd use about all of them. I heard that there is a 0W-30 for diesels that would be good if it's that cold -- you might investigate that as well. Use that genny if it's -40 for the block heater. Don't know about the CTD, but one of our members here starts his truck up in NH at -20 with no problems without a block heater. Now at -40, you might need some help, thus the genny idea. I wouldn't think it gets that cold that often. Of course, you might go ask in a CTD forum. They'll probably know the specific issues/limitations with that engine.
I just did a little Googling -- check this one out:
https://lubricationspecialist.com/fr...aspx?fileid=67
Pump runs off the battery, but it uses fuel for heating. That makes it much easier on your batteries. That's important because at -40, there won't be a lot left after running a 1000W heater for 2 hours...
Senior User
Joined: Apr 2006
Posts: 143
Likes: 0
Well I just stumbled on this.. Magnetic Block Heater - MH1153 I already have an inverter thats good to 300 watts and I don't think an hour or 2 of 180 watts would kill the batteries, but where do you put that thing? Side of the oil pan, on the engine block? Oil pan I think would work but just can't get it through my head how much iron there is between the engine block and the coolant inside it.. Where else can I put it?
Fleet Mechanic
Joined: Feb 2007
Posts: 1,852
Likes: 39
Regarding using the batteries to warm the engine; there's just not enough energy in them to do any significant warming. To match the wattage going to a stock block heater, you would have to pull about 80 amps continuous from the batteries.
I like the synthetic oil and generator solutions. And I would also be running a trickle charger, but I would be running that overnight for sure.
I did a mod and posted it to the forum, adding a Marinco plug, a switch, and an onboard trickle charger to my truck. Using the switch, I can select whether the cord is powering the block heater and the trickle charger, or just the trickle charger.
Here's the mod:
https://www.ford-trucks.com/forums/7...ater-plug.html
I like the synthetic oil and generator solutions. And I would also be running a trickle charger, but I would be running that overnight for sure.
I did a mod and posted it to the forum, adding a Marinco plug, a switch, and an onboard trickle charger to my truck. Using the switch, I can select whether the cord is powering the block heater and the trickle charger, or just the trickle charger.
Here's the mod:
https://www.ford-trucks.com/forums/7...ater-plug.html
New User
Joined: Dec 2008
Posts: 1
Likes: 0
7.3 block heater alternative
I found a better option since you're in such a cold area. Look @ espar.com and look at the hydronics5 heater. Uses about a 10th of a gal an hour and three times the heat of any plug in block heater. It's pricey at $800 to $1000 but with what you are doing it's a steal compared to buying a generator. Good luck