Diesel block heaters Options

[rpoz-29]

My '96 Dodge Cummins is a pain to start cold without using the block heater. I assume it has a heating element, which makes me curious about how much current it uses. How long does it take to bring the engine temp up, and can it, or should it, be left hooked up for days without starting?

[mustbnutz]

My '04 DMax recommends the heater be used if temp is below -20F.
Should be plugged in for min 4 hours at that temp prior to start. Recommend 8 hrs.
Some folks I know keep theirs plugged in all the time if temp is under +20F as they have starting problems.

[1qwikbird]

My 97 Dodge/Cummins is similar. I bought it used with 160K on the clock 3 years ago it is the first diesel I have owned. The first winter was a learning experience. First thing I did was buy a heavy duty programmable timer and started with it 6 hours of preheat and now I have it down to 3.5 hours of preheat. For me, in central NJ there was little added benefit beyond that. And then I made the switch to full synthentic oil, that by itself was a dramatic difference. Now unless it is supposed to go below 20 degees I don't even really need to plug in. When I do plug in, its like a summer morning. She spins fast, kicks right over with a little pedal and is ready to go without the locomotive like smoke and noise or the extended warmup. Cabin heats comes quicker too with the plug in. I haven't noticed any real jump in electricity on my bill so don't let that be a deterrent.

The block heater warms the water direclty, not the oil, so to leave it hooked up for extended periods isn't going to hurt anything, maybe shorten the life of the block heater, but not much else. I think it is rated to bring the water up to around 100 degrees? The block and oil and everything else is heated through convection.

I love my 12v cummins. Best diesel out there, bar none. Might be sound like a cement mixer, smoke a bit, but simplicity has its advantages.

[billy_ocean]

I love my 12v cummins. Best diesel out there, bar none. Might be sound like a cement mixer, smoke a bit, but simplicity has its advantages.

my buddy had one of these in college, man that is a sick motor. i got to walk through the cummins CDC in north carolina, and saw them using that motor in 600hp marine applications.

i doubt there'll be another diesel engine like that in a pick-up ever. nice catch.

[Eskimo]

I had my block heater on a 15 amp outdoor timer.. it turned on 4 hours before I'd leave in the morning, which was enough time to bring things up to temp in the Raleigh, NC area on 30 degree mornings.

IIRC, the block heater is a 750 watt draw.

And yes, you can leave it hooked up for days.. the electric company will love you!