Block Heaters

[rmonio]

I've had my block and hydraulic heaters installed for several years on my 4600, Highlander, and they have really been a timesaver for me. I'm sure you'll find that the money spent on plugging them in (mine have been sometimes overnight) is well worth it.

-Bob

[Egon]

I have always wondered why a block heater makes the engine easier to turn over and start yet the engined oil is not warmed??

[Dusty]

The engine oil is warmed as a result of the block becoming warm. The reason that they start easier, is that with cold everything shrinks. When it gets warm, the metal expands and allows the engine to turn over easier. When I lived in NH, some winter mornings were so cold, that I would have to take a shovel of hot coals and put it under the engine oil pan. Once you heard the oil start to "crackle" you knew it was warm enough to start. That usually took the better part of a half hour or more. My old '55 Chevy wasn't used to the cold having originally come from the South. When I purchased it, it didn't even have a heater in the passenger compartment. It was what is known as a heater delete car. I had to get one from a junk yard and install it. That was a real pain, but I learned a lot from the experience. One, of which was to always check any rust free Southern car to make sure it had a heater! I wish that I still had that car today.
Dusty

[Egon]

Would not everything shrink or expand in the same relationship be it hot or cold?

[Dusty]

I would say that the relationship would be different. Different metals expand and contract at different rates. In the hypothetical engine block it might be iron and the connecting rods aluminum and the pistons steel. The bearings are made of a babbitt composition material, etc. All these items will expand and contract within the engineering limits to allow for starting at all temperatures, but it is the cold that is actually that will inhibit the combustion process from happening fully at the lower temperatures. That is why they bang and run rough when first started when extremely cold and smooth out as they warm.
Dusty

[gemini5362]

Ok since I live in Arkansas and Dusty posted about heaters in Arkansas I dont have much experience with block heaters. But I do have a question. The pipe heaters that you tape to your pipes to keep them from freezing have a thermostat on them. You just leave them plugged in and when the pipe gets below a certain temperature the heating elements turn on. Do block heaters not have the same setup ?