How does a blockheater work

[trocar]

I have one, but have never used it, and have never really thought about it before, but I have no idea what they do. Can someone give a fast lesson on what they do. Is it as simple as keeping the oil a few degrees warmer????

[joatmon]

some general discussion at http://oee.nrcan.gc.ca/english/media/block.cfmsome block heaters actually put a heating element into the coolant passage of the engine. The Vibe/Matrix OEM block heater doesn't, it is just a heating element that is clipped to the outside of the engine block. Does the same thing, but in a little different way than most. I don't have one, but don't really need one here in tropical Maryland

[DavidPIL]

Hi Joatman,I installed the OEM heater in mine, it didn't clip on the outside, it actually was a round metal probe about 3-4" long that slid into what they called a freeze plug, or a hole bored into the engine block. Although it isn't a heating element in the cooling system, it does slide into the engine block, almost becoming a part of the block itself.Trocar, from there, the probe transfers resistance heat to the Aluminum engine block from that freeze plug (bored hole). I'm not sure how warm the Block Heater actually gets but it does help starting the vehicle and makes idle warming almost unneccesary.I use mine when the high temp of the day isn't going to be above 30 or so.Dave

[ToolGuy]

The block heater either installed into a freeze plug hole or a tapped hole near the thermostat housing and heats the coolant around the engine block. Therefore when it is plugged into a 120V outlet and left for awhile, heats the coolant around the block causing the engine to warm up quicker, ease its start and produce heat faster into the cabin for you. Good thing to have in cold climates.

[trocar]

Thanks for the info, Think I am going to star using it

[Altus]

Yup what they said - it's basically just a high-powered immersion heater in the block to heat up the coolant.