Block heater

here is the most common heater on the market. Used by both Detroit and Caterpillar:

3406 Cat Block Detroit Heater 1500 Watt With Plug - 4 State Trucks

 

The more I hang out here. The more I realise I dont know jack.

 

When I had older trucks, like say pre 2000 then I would plug in under 30 degrees. With the newer trucks I don’t even think about it anymore unless it’s getting below 15.The batteries normally take a #### and won’t crank fast enough before the engine won’t fire due to the cold.

Are newer emissions engines higher compression then the older preemissions ones? It’s pretty incredible the difference.

 

It wasn't until recently that I heard you shouldn't run a block heater with the engine running. I've been doing it for years on my personal vehicle with no ill effects so far.

 

I bought a brand new 1994 Ford F-150 6 cylinder stripper. Installed the block heater. Everything was fine until the first time I forgot to unplug it, burned it out immediately. ON the Cummins in my 4070B, it didn't seem to make a difference. I am only guessing the location of the element and the turbulence of the coolant in that area are the keys. Some vehicles are more prone than others.

 

Interesting, I'll make sure to unplug before starting. I do unplug before starting anyways, but good to know and keep that in mind.

 

After you plug it in, you can feel around the element that goes in the block and it will be warm to the touch. Most will make a sizzling sound.

 

Same element used on electric water tanks, only shorter version. @Studebaker Hawk said it all. A few hrs is plenty.

 

I'm going to call myth on this. Not that heater elements don't burn out--they do, although nowhere near the frequency they used to--but if you've got that much potential to create that much cavitation around a heater element, then you've got far bigger problems brewing... like pitted liners.

If anything, cavitation will reduce by circulating the coolant and extend the life of the element, due to two facts:

• Circulating the coolant will reduce the localized heating produced by the element
• Cavitation reduces with lower temperature

- Cavitation - an Introduction​

I'm not suggesting running your engine up to full temperature and having the block heater plugged in the whole time, but for the few minutes engine and block heater operations coincide, there's not going to be an issue. During this recent cold-snap (-32 C/-25 F overnight). Remote starting our little diesel pickup and running ~5 minutes with the block heater plugged in barely moved the temperature needle off bottom. In many years of Arctic region operations in far colder temperatures, I am not aware of any block heater failures due to combined operations.

I am sure the real reason for the warning is the number of people that improperly route heater cords causing burned cords on exhaust systems or wrapped up in fans and/or drive away while plugged in.

That's why I tell people to route the cord in a way that they absolutely will see it before getting in their car; like putting some wraps around the sideview mirror. Which is all well and good until they rip their sideview mirror off.

As always, YMMV.

 

@not4hire we got hit with the same cold snap. Even my gas pickup plugged in overnight and idling for 10 minutes barely gets the temperature needle 1/4 the way towards operating temperature. My last gasser up in northern Alberta never got plugged in even at -40. Just ran 0W-30 and a big battery. Started every time.