I have this old tube that is designed to heat the engines oil. I've never used it before, but I think its a good idea since its 15 degrees during the day around here. You plug it into an extension cord and stick it in the dip stick tube. It will help my engine heat up faster and as a result get better gas milage during that time.

Anyone heard of it or tried it? I've gotta find it soon, it's buried in the basement.

 

Yeah, once or twice; I didn't think they would even let you buy a car in Canada without one. Although, the factory-installed ones are a bit more elegant, there's a plug behind your grille that you just plug in, much less hassle.

 

I assume that plug is there only if it was factory installed.

 

Oil dipstick heaters tend to cook the oil and create problems. The other problem is that the oil lays in the pan, and loses most of its heat to the air through the pan.

The best heaters I've ever used were the tank-type heaters that cut into the coolant hose to the heater core/water pump return fitting. They heat the coolant in batches, then convect/pump it out to the engine through the check valves. Care must be exercised on installation so they check valves are installed to flow in the correct direction, but they only heat coolant in the block instead of the radiator. They don't impede normal coolant flow, and the power cords are usually easily removable/replaceable. They are also easily installed and removed without losing coolant. I've had many of them, and never had a better type.

The freeze plug types don't circulate coolant, but are the second best since they warm only the block. They are the most difficult to install, and the cord is usually necessarily routed too close to the exhaust to survive the summer driving.

The lower radiator hose type heaters lose much of their heat to the radiator and don't heat the engine as well. A 600W tank heater is far more effective than a 2,000W lower hose heater. Additionally, all the coolant must be drained or is lost during installation, and the potential impediment to full lower hose flow can be an issue during the summer months.

Having a warmer block instead of warmer oil allows the engine to spin more freely, since the oil that would normally glue the rings to the cylinders is kept warmer and thinner. Friction from pumping cold oil is not nearly as difficult high as friction from rings that are bonded to cylinders with Jell-O. And once the oil hits the warmer block, it doesn't take long to get it thin and pumping. Trying to heat the entire engine with four quarts of moderately warm oil sitting in a sump is a lot less effective than heating the entire engine casting with 15 quarts of coolant distributed all through the block and heads.

Katz engine heaters are a good brand of tank-type, but there are many other good ones. When I was in Oshkosh, serious drivers used only the tank-type.