What is this?... its off the GM site.


"How long should I leave the engine coolant heater plugged in during cold weather?

Usually the coolant heater should be plugged in a minimum of four hours prior to starting your vehicle. However the time may vary depending on the outside temperature, the kind of oil you have, and some other things. A dealer in the area where you'll be parking your vehicle can give you the best advice for that particular area. "

 

I think some option included a block heater that you plug into 120v AC current in cold climates to keep the engine fluids warm. I remember My Jeep CJ had one.

 

I have a bracket racing buddy who uses one on his alcohol car to keep the engine temp consistent.

Rich

 

not too much expansion and contraction if everything is kept at a certain op. temp.. mostly due to clearance's w/ race car's and i know the diesel's use block heater's as well..not sure why though

 

Why do diesels use block heaters? Is it because there is so much heat generated with compression that if the block temp is below a certain temp the sudden change in delta T can cause the block to gain stress cracks and eventually crack the block? I dont know just a thought but if someone knows the real answer i would like to know. After all i learn most of my information from you guys on this board

Brandon