Engine Block Heater

There are downsides to leaving your block heater plugged in continuously; the increased electrical costs and a shorter (number of years not hours) lifespan of the heater. A warm diesel is a much happier diesel when started. The block and head are warmer as is the oil. We had a twin Detroit powered fishing vessel that was plugged in all the time. The marina restaurant complained about the amount of unburned fuel coming out of the pipes after start up. Leaving the block heaters on all the time eliminated this issue and made everyone at the marina happier.
Randy

Not sure what Caterpillar installed on their engines, but the block heater on my Cat engine does not trip the circuit breaker at my home. Regular 20 amp circuit breakers. Not that I leave it on all the time, but I did forget the switch on accidentally and it did not trip the circuit breaker.

Here is a website with a number of block heaters. The one I put in our coach was a 1000 watt heater, though a 1500 watt was optional.

http://www.hotstart.com/en/home/products/in-block-heaters/

Sully2 wrote:

2oldman wrote:
EB heaters take a lot of power.. 1000w or more. Be careful.

Untrue. I had one is a V8 Ford that was only 300 watts. And the one for my DP sure aint no 1000 watts

If your block heater is OE it likely IS 1000 watts.

Side note- when you attach a cord to movable equipment - use only inline plugs and secure the cords right behind the plugs with strong ropes.
This way when you start driving with the plugs still in, the ropes will disconnect the plug without breaking and sending sparks around.
If you use it often - sooner or later you will forget.

Even at 8°F, I only switched on my block heater (mine has a switch) about 30 minutes before starting. Or 1 hour if I wasn't in a hurry. With my Cummins 5.9 it really didn't take long to heat it up and it would turn over smoothly. Mine is like 750 watts so that's only 6.25 amps and as long as you don't run an electric space heater, turn on the coffee maker, or the MW, a 15 amp circuit should handle it fine for that short time before starting.

So that's my recommendation. Don't plug it in until 1 hour before starting the engine.

2oldman wrote:
EB heaters take a lot of power.. 1000w or more. Be careful.

Untrue. I had one is a V8 Ford that was only 300 watts. And the one for my DP sure aint no 1000 watts

Thanks to all for the responses. It helps much.

I live near the beginning of the Alaska highway. Perversely me we are enjoying warm weather right now - high of 5C today!

Anyway, engine block heaters are a must here. We plug in when temps get down to -20 C, 0 F. I commonly have two vehicles plugged in to the same 15 amp outlet so the power draw must be well under 1000 watts. When working, you should be able to hear a soft hissing sound with the hood open. The usual cause of failure is the plug on the end of the cord.

Cold weather calls for a good battery. We normally replace batteries at age 5 years and I watch the resting voltage (8 hrs after engine is shut off) to make sure it is near 12.6. It takes at least 20 minutes of driving to replace the energy used to start the engine.

Fire engines have block heaters plug-in 24 hr a day 365 days a year, but they can afford the energy use.
I had my Ford 7.3 l diesel engine starting at -25F, but it took almost whole capacity of 2 new batteries to have it running.
I think at 8F block heater might be more hassle than help, but it will help.