Engine Block Heater ?
Hotshot
Joined: Nov 2013
Posts: 10,107
Likes: 96
From: Hempstead, TX
When I plug mine in, I don't feel any warmth from the plug or cord the next morning, or any heat escaping the engine compartment. I also don't see instant heat blowing from the registers. What I do see though, is that the engine warms much faster. Once I begin my trip, I have warm air within minutes, and the coolant temp gauge shows normal after only a could of miles, instead of several. (Never checked the actual coolant temp though - just referring to the needle). With my old 7.3, I felt the plug and cord get warm, and felt heat escaping from the engine bay after a few hours. I think the 7.3 had a larger element though, and also worked on the oil by way of the cooler assembly. As I recall, the element was built into the oil cooler, so it warmed the coolant and oil together. (Been a while since I had my 7.3)
Lead Driver
Joined: Jan 2010
Posts: 6,600
Likes: 84
If I remember right, and I'll try to remember to verify, the coolant needle at half is around 170°F.
I consider operating temperature around 195°F since that's where it levels out and tends to stay under 200F without towing or payload.
Edit: Except I may be thinking about the oil temps. Will have to check now.
I consider operating temperature around 195°F since that's where it levels out and tends to stay under 200F without towing or payload.
Edit: Except I may be thinking about the oil temps. Will have to check now.
Posting Guru
Joined: Jan 2010
Posts: 1,616
Likes: 6
From: Whitecourt AB, Canada
Just do the test. I did this with the first winter my truck experienced so I would know how much power the block heater was using (and therefore dissipating, since resistive heaters are pretty much completely efficient). P=I*V.
Senior User
Joined: Jul 2012
Posts: 233
Likes: 0
That depends on the ambient temperature. If it's zero degrees outside, I doubt if the engine temperature gets much past 40 or 50 degrees. The heating element is only 850 watts which provides about 2900 BTUH. That's not very much.
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Lead Driver
Joined: Jan 2010
Posts: 6,600
Likes: 84
It's an element attached to an electrical cord.
Senior User
Joined: Jun 2006
Posts: 176
Likes: 0
From: Schaefferstown, PA
Yesterday morning the temps were in the low teens so I, just for kicks and giggles, plugged the heater in on a timer to turn it on 4 hours before I planned to go out. The ScanGauge II read the water temp before I started it up at about, IIRC, 85 degrees. As soon as I started it and the water started to circulate it dropped down to the 50's in a few seconds. As mentioned before, the heater started to blow warm air much quicker then days when it was not plugged in.
If not for the ScanGauge I would have had no indication the heater was working. The cord and plug were cold and no snow had melted off the hood.
If not for the ScanGauge I would have had no indication the heater was working. The cord and plug were cold and no snow had melted off the hood.
Posting Guru
Joined: Jul 2013
Posts: 1,726
Likes: 2
From: Connecticut
I haven't plugged in my 2011 f250 yet waiting for single digits.
In my 02/ 7,3 I would plug it in for 4 hours prior to starting, and it would fire right up. It made for easy starts and within two or three miles I would have heat. Noting you had to strain your ears to hear a faint humming sound when running.
The one thing that I found out quick with the 7.3 heater was that your first electric bill after plugging it in all night was a whopper. So bought a timer and set it for 4 hours and it worked fine.
I do believe from what I've read that the new heaters are smaller in output.
In my 02/ 7,3 I would plug it in for 4 hours prior to starting, and it would fire right up. It made for easy starts and within two or three miles I would have heat. Noting you had to strain your ears to hear a faint humming sound when running.
The one thing that I found out quick with the 7.3 heater was that your first electric bill after plugging it in all night was a whopper. So bought a timer and set it for 4 hours and it worked fine.
I do believe from what I've read that the new heaters are smaller in output.
Cargo Master
Joined: Jan 2007
Posts: 1,945
Likes: 1
From: Wasaga Beach, ON
Plugged mine in this morning. Only for an hour before I left. Outside temps -17c, engine temp when I started it was 48F. Engine temp when I got to work after 5km driving was 130F.
When started at these temps the idle is 1175rpm. Was still at that idle when I parked at work. Is this the normal idle rpm when the engine is cold?
When started at these temps the idle is 1175rpm. Was still at that idle when I parked at work. Is this the normal idle rpm when the engine is cold?
Elder User
Joined: Apr 2013
Posts: 714
Likes: 1
Plugged mine in this morning. Only for an hour before I left. Outside temps -17c, engine temp when I started it was 48F. Engine temp when I got to work after 5km driving was 130F.
When started at these temps the idle is 1175rpm. Was still at that idle when I parked at work. Is this the normal idle rpm when the engine is cold?
When started at these temps the idle is 1175rpm. Was still at that idle when I parked at work. Is this the normal idle rpm when the engine is cold?
Cargo Master
Joined: Aug 2010
Posts: 3,228
Likes: 64
Page 30
Cargo Master
Joined: Aug 2010
Posts: 3,228
Likes: 64
Don't know if it is valid on these trucks, but .............
On truck block heaters you can't run the engine with the heater on. The water flow around the element creates cavitation, and the momentary lack of coolant around the tube cause the heaters to burn out.
Found that out the pricey way on my twin Detroit 6-71 boat.
On truck block heaters you can't run the engine with the heater on. The water flow around the element creates cavitation, and the momentary lack of coolant around the tube cause the heaters to burn out.
Found that out the pricey way on my twin Detroit 6-71 boat.