Testing my engine block heater?

[1996ex]

How do I test that my engine block heater is working?

I ask because I did something kinda dumb (we're all here to help others when we do these things!), and I just drove it home and plugged it in to test it. But obviously the engine is already warm :/

Any thoughts? This is a 2003 4.0 and I'm only just using the block heater for the very first time and hoping it works!

 

[94Eddie]

Plug it in and use a laser thermometer to see if the block is heated above ambient temperatures. I would wager it still works. I suspect many people in cold climates using block heaters park their vehicle, plug in the heater and go inside.

 

[1996ex]

Plug it in and use a laser thermometer to see if the block is heated above ambient temperatures. I would wager it still works. I suspect many people in cold climates using block heaters park their vehicle, plug in the heater and go inside.

I actually don't have a laser thermometer.

Does the block heater warm up more the oil or the coolant? Because if it's the coolant I can check to see if that warms up from cold on the gauge.

 

[94Eddie]

The block heater directly warms up the coolant. The coolant warms the oil and other engine areas. The heater isn't meant to heat the block to operating temperatures so it might not cause the temp gauge to move. Especially if the ambient temperature is very cold.

 

[1996ex]

The block heater directly warms up the coolant. The coolant warms the oil and other engine areas. The heater isn't meant to heat the block to operating temperatures so it might not cause the temp gauge to move. Especially if the ambient temperature is very cold.

Damn thing seems to work and pretty well! I let it sit in 35-40 degrees for three hours and the coolant temp was still about 1/5 to 1/4! So it seems to have kept it warmish all that time! I'll take it!

 

[boominXplorer]

Be careful, they draw a ton of power and will add to electric bill for sure if you keep it plugged in

 

[TechGuru]

Amp meter.