I noticed last night we have them at Autozone, and the farm stores have them as well. Tractor Supply, Northern Tool, all those places have them. They do work well, have a tractor that the hydraulics don't work well if the oil is cold, so I put one of those under the belly, and it takes off just fine.

 

Most autoparts stores should have them, or be able to get them.

I think they are about $35.

The last one I got was the magnetic kind, and then you just put it on and run the cord up into the motor compartment, and out the grill for the few months a year needed, and then take it off when it warms up.

That way I can put it on other vehicles if needed.

 

I just saw this one while looking at the Canadian tire site.

Canadian Tire

The down side is it would hang too low to mount to the bottom of your oil pan, so it would have to be put on the side.

But its rather cool that it has a thermostat in it, to keep it at whatever temp you desire.

 

Although heating the oil/pan will make it crank over easier, I have a hard time believing that heating the oil in the pan will effectively add heat to the cylinders as well as a block heater - which heats the water in the head and block that is in direct contact with the cylinders. If it isn'tadding heat to the cylinders, I don't really see how it will help that much raising the temps high enough for auto-ignition of the diesel - which is what is really needed to get it started without glowplugs...

 

That's my thoughts too.
It seems an oil pan heater would make a gas or diesel engine with a functioning pre-heat system (glow plugs or grid heater) start better/faster but I doubt it will help the compression ignition.

When my glow plugs were out in my '86 I could plug in the block heater and it would fire up. It had to be over 100* outside for it to SOMETIMES fire with out the glow plugs or block heater.
I couldn't belive it had to have glow plugs or block heater at 90+* but it does.

I just think you're going to have to heat the water/coolant to get the heat required BUT I could be WRONG!

 

Any heat you can add to the engine will help.
The big question is, will it help enough for the engine to start?

Yes the heat from an oil pan heater will raise the engine temp, heat rises and metal conducts heat.
Will it raise the temp enough for it to fire, probably if you are not in an extreme cold area.
If you are in an extreme cold area, I think I would go with a lower radiator hose heater.
And I would mount the heater as close to the block intake as I could so the heat would go up in the engine by convection.

I have seen people use charcoal grills.
I have seen fires built under motors.
I have seen floodlights and quartz lights used.
I have seen heat lamps used.
I have seen hot boxes that run off of diesel fuel to warm the coolant.
And I have seen kerosene fired torpedo heaters used.

Several of the above have a high fire risk.
Some are not the route I would have gone or even advise.
Several of the above do not work well if the wind is blowing.

In here I have heard of hair dryers and heat guns in the intake to warm the air.

I have started several big Cummins, Detroit and Cat motors using the kerosene torpedo method with good results, but wind can play a big factor there as well.

In the end, you need to get heat into the motor so one compression stroke can go from ambient air temp to 500 degrees so the fuel will ignite.

A working glow plug system and a good battery system have never failed me on my IDI.
The block heater is a very good backup system, and I really like it in the winter when I have to go plow, as soon as the engine starts, the defroster starts thawing the windows.

I just happened to think, the best one of all is a heated garage.
Windows clear, interior warm and all snow or ice melted off the vehicle exterior.

I know, I know you don't have to tell me.