Engine Block Heater

I read in here that most engine block heaters have a built in thermostat

Ive never heard this

None of the ones I’ve had (factory installed) had thermostats. Just a coil heating element and its on when its plugged in and off when its not. That’s why you’d put it on a timer or get up at 2:00 to plug it in. I think some of the after-market coolant heaters might have had a thermostat but can’t say.

On in On
Off is Off
That was my thinking

The ones that go into the block do not have thermostats. For a V8 engine they are only 400-600 watts, and the engine ones do not really get hot; just warm to the touch.

Since you only need 1.5 hours of heat to get it up to the desired starting temperature, a timer will have you a lot of money. We set it to come on at 6 am when we leave the house at 7:30 am.

At 16 cents per kwh, leaving a block heater on from 7 pm till 7 am will cost you $35 per month!! Having it on for 1.5 hours will cost you just over $4 per month.

Some of the magnetic oil pan heaters (which I don’t recommend) have built in thermostats.

Here (where it gets to -50 or colder they recommend 1hour per 10 degrees below 0

@bad bearing Yes, in your case I would recommend a longer time. In the far North when I worked there, cars were left plugged in all night. However, hotels and businesses cycle the power supply to 2 minutes on and two minutes off.

That makes sense. I see people here leave the car plugged in all night when its above zero (my neighbor would be one)
I guess they don’t get it

I unplugged my oil pan heater because i was worried that 75 watts might be to much and the dang thing has a protective cover so as to keep me from putting it on the bottom of the sump.
With 5-30 amsoil and a block heater i figure i should be fine

@docnick I know this is off topic but… Whoa! 16 cents per kWhr! I don’t know where you live but I’m sorry about your utility company. I just signed a contract for 6.49/kWhr for 2 years in Ohio

@Mustangman We actually pay 8.1 cents per KWH, but we get a very complex bill with all sorts of surcharges, which brings it close to 15 cents. Check your own total bill and divide by the KWH used. Many jurisdictions now use 12 cents as a going rate. The stickers on fridges for cost per year for power use about 12 cents.

Denmark has the most renewable power and also one of the world’s highest rates at 58 Cents per KWH for domestic users.

Friend says I have a blockhead heater - the incandescent spotlight bulbs I have shining up onto the bottom of the emergencyehicle engine and transmission.
Also have a magnetic heater which I stick to the oil pan with a broom handle. Pulls off with an attached rope.
Unfortunately, they are on all night because I never knowhen the vehicle will be driven.

Is he related to red green

He needs a timer that turns off then back on as mentioned earlier. If said Bulb gets hot enough to keep the engine warm it could be a fire hazard. Although Possibly Red Green approved…not recommended

I used a magnetic oil pan heater in Alaska. It was on the truck when I bought it and the guy epoxied it on for some reason or another. I agree with @Docnick about not recommending one though. It worked (sort of) but my block heater worked much better when I lived in Northern Maine. I left them on 24/7 once the temps got down to zero. My utilities were included in my Alaska cabin rental and I lived on-base in Northern Maine so cost was not a factor.

A magnetic oil pan heater worked good for me. In very cold temps the cord cracked. (i duct taped it) It was just a temp. way to heat the oil but it worked pretty good. Agreed its not the best. Not when you can permatex a heating pad to the oil pan … run the cord and be done.
Block heater warms the block Not the oil

Off topic here but I just looked at my last electric bill and after the service charge, etc., electricity here in the Seattle area is 8.8 cents/kwh.

Im not sure what it is here. But we have i believe the highest rates in the country. I will look it up.

General Discussion

GVEA Rate Schedules
Service Type Customer Charge Utility Charge Fuel & Purchased Power Charge Effective Rates* Demand Charge
Residential $17.50/month $0.09724/kWh $0.10576/kWh $0.20300/kWh N/A
GS-1 $20.00/month $0.09637/kWh $0.10576/kWh $0.20213/kWh N/A
GS-2(S) $30.00/month $0.0523/kWh $0.10576/kWh ** $11.94/kW
GS-2§ $30.00/month $0.0523/kWh $0.10576/kWh ** $11.94/kW
GS-3 $295.00/month $0.02458/kWh $0.10576/kWh ** $19.11/kW
*Effective Rate is the sum of the Fuel and Purchased Power Charge ($0.10576/ kWh) and the Utility Charge.
**In addition to the Fuel and Purchased Power Charge ($0.10576/kWh), Utility Charge and Customer Charge, GS-2 and GS-3 members are subject to a Demand Charge.
Tip: Use the Bill Calculator to get a better idea of how much your total bill should be based on your service classification and usage.
Last updated: 08/31/2013

"Is he related to Red Green"
Think I'm his illegitimate son.

(Ford charges a fortune for their engine block heater and much for their special connector to it.)

No fire hazard because no combustibles and nothing gets hot enough to burn.
To keep warmth in, I lay a sheet over the hood and radiator.

The magnetic heater indicates nothing about an internal thermostat.

(Ford charges a fortune for their engine block heater and much for their special connector to it.)

Isnt it just a frost plug heater?

Any leak would be a potential fire hazard. If light gets hot enough to start your engine it gets hot enough to start a fire.
I used to use a pan of charcoal under the engine back in the day. I was on constant surveillance for fire.

Correct. No thermostat on magnetic heater.

illegitimate son…lucky dog