Installing a block heater '01 2.4

I want to install this block heater I just purchased but I have no idea where it goes!



Can anyone help me locate the core plug?



Like it says in the title I own a 2001 cavalier 2.4L DOHC.

The Haynes manual may tell you where but I doubt it. Most shops that install one will look it up in a manual. If there is an available / accessable frost plug in the head, it could go there. Most GM cars do not need one. If temperatures don’t go below zero, you might not need one.

Look at the engine block between the cylinders. It will look like this:

Sadly I moved to North Dakota so below zero is a daily occurrence

Thanks for the pic but I don’t think that will work. The heater plug made for the car is threaded and in the research I did that wont work in the hole made by those since the caps are not threaded.

Did you purchase this on eBay or something? If this plug is specific for this car, the instructions should be fairly detailed where it goes. Most of the block heaters I’ve installed replace a freeze plug, or core plug, and either come in different sizes for different engine plug sizes, (there is quite a variety), or this heater should have different adapters to fit the various different sizes of freeze plugs. I suspect you’ll have to ask a technician at the manufacturer for clarity.

That looks like it might replace the block drain plug. Did you get any instructions with it? Where is the electrical connection?

It does look like it replaces the block drain plug. If that’s the case I would wonder how efficient it is considering how small the drain plug is.

I would consider getting a core plug heater instead, it is harder to install but it is bigger and would provide more heat to the cooling system.

Certainly ZERO is a rarely occurring phenomena here but for safety’s sake the local ambulances had block heaters installed. They were
mounted in the lower radiator hose so as to allow the heat to rise into the block. The crews were very pleased with them. The diesel engines started easily and the heater/defroster system was functioning from the moment they started the engines. Are the hose type heaters not
available for automobiles?

From what I recall about these type of heaters, was the newer model cars will not let the warm water circulate in the block once the engine is shut off. Don’t know how true that is.

Attached is a picture of the back where the electrical connection is located. The size of the threaded portion of the plug is between the diamater of a penny and a nickel.

I purchased it at O’Reilly Auto Parts and the instructions that came with it were so bad that it is impossible to follow.

Through some further research, looking at other manufacture’s installation instructions, it seems the heater plug is installed in the water pump. Has anyone else heard of this?

For anyone else who is looking to install one:

The installation is actually very easy and can be done in 20 min.

Look under the exhaust manifold at the water pump. On the housing you will find a plug with a hole to fit a 3/8" socket. Unscrew the plug and install the block heater in its place. It’s just that easy.