I have a quick question/opinion poll about using my old factory block heater. The short of it: I have a 1990 F350 with a 460 in it, and it came with a block heater, which has not been used for quite some time. A couple years ago, the passenger's side freeze plug/heater element sprung a leak and was replaced with just a standard brass freeze plug. My two questions are: Is it okay to/would you run an old block heater in only one side of the engine, and is it normal for this heater to make a hissing-like noise when operating? It sounds like water boiling in an electric kettle. I am just concerned about this because like I said, this equipment has not been used for a long time. The reason why I am using now is because we are in for some pretty low (sub-zero) temps here in Anchorage for the next week, and I would like to give the truck a little boost in the morning. Any and all thoughts/comments are appreciated. Cheers!

 

Yes, you will hear them "cooking" I personally have never seen one with more than 1 freeze plug heater.....If I am not mistaken that's how Ford sends them out of the factory ........there may have been an option for 2 of them ......not sure.......and I'm sure that someone somewhere has installed 2 at some point.......you are fine!

 

^^^^^^ What he said.

Mine has only one, passenger side. There has been discussion about 2, and it's overkill.

 

Maybe not in Alaska.

​​​​​​​Remember, -40 is the same in the U.S. & Canada

 

It gets to -40 here once in a while, 1 block heater is plenty.