Oil heater

[mottofreee]

I want to make an electrical resistance for heating the oil.
A flat device (1.2" thick x L: 63" W: 39") located at low height in the oil bath.
The estimated power is 200W with 12V power.
The maximum operating temperature is 100C, I hope to warm up the oil in a few seconds (30 ... 60) - for the battery protection I just will not use 2 batteries: one summer (12V / 50Ah) and one winter (12V / 75Ah) ...
Now I'm thinking about the possibility of optimal heat transfer.
Classical heating resistors have a yield of 0.75 (that is, 200W is transported in oil than 150W).
If the heater is outside the oil bath,that is, you heat the steel that heats the oil - between the resistance and the steel wall the thermal contact is faulty but the contact between the steel and the oil is ok.
However, only one heater part is in contact with the oil bath .
On the other hand, the ultra-flat device, located in the oil sump, which is covered in oil , the transfer is maximum.
So I see the problem and I'm sure there are other issues.
Any opinion is welcome.

[tolsen]

Car battery as energy source won’t work.
About 80 Watts is enough if you can insulate oil pan and reduce heat loss.

[mottofreee]

Indeed, the type of original battery will not cope.
Currently I have no access to the 230Vca network and in the near future.
I'm looking for materials to isolate the oil sump.

[tolsen]

Better heating engine with a Primus stove placed under sump.

[tolsen]

Stick on heater 220:240V 250 Watts. https://m.ebay.co.uk/itm/Engine-Oil-...wAAOSwldRaB~km

[mottofreee]

I do not have access to the 230V network. If I had then the first option would be:
https://www.aliexpress.com/item/Newe...StoreLevelAB=0
Heat the engine 100% ... starting like summer. An automation with a WiFi relay on the phone. So you can not get snow clear, remove the ice and the in car is already warm.
Material for oil bath isolation we still have no ; alternative is a composite oil sump.
what could I isolate the oil sump?
Composite sump is ok in time? The price of one is 66GBP + transport (~ 35 GBP) a high price; I think one of the steel is 25 GBP and the store 10 min. away from my house ... https://www.epiesa.ro/baie-ulei-smar...rod-102661813/
So, what can I thermally isolate the steel bath?

[tolsen]

Use Primus. No need to insulate.

[mottofreee]

Car parking is joined to the road (with a common side); there are cars and people on the road. https://www.google.ro/maps/@46.76656...7i13312!8i6656 The picture is from 2010, there are now more cars (* 5) on the same roads . The hole is 3x4m (in papers) . The actual width is 2.2 m. On the left is a car, on the right another car, behind the curb, in front of cars / people.
Primus is impossible to install.
The feasible variants are:
- the Webasto preheater on diesel
- preheating oil at 12V
From previous discussions I understand that thermal insulation of oil baths helps a lot.
What are the fit materials/or which qualifies for this?

[tolsen]

I have painted my sump in several coats of 2 pack epoxy plus applied a thick coat of bitumen. This works for me as I have fitted heater inside oil pan. You may recall my heater is a 150 Watt PTC towel rail heater element which can be allowed to run dry as the PCT element will self regulate heat and not burn out.

When away from 220/240 V mains power I simply use my military style kerosene stove to preheat engine when necessary. This kerosene stove is very shallow but to avoid hot spots and setting fire to my bitumen coated oil pan, I place a steel plate on top of the stove to spread the heat out a bit. Of course I only run the kerosene stove in attended mode. One can also fry bacon and eggs whilst preheating engine and enjoy a good breakfast out in the open.

[tolsen]

Best heater is this one:

[tolsen]

3000 Watt so engine is heated in no time. Unlike gas operated heaters this one works regardless of how cold.

[mottofreee]

Winter epoxy + bitum resist but in summer the oil heats up to 120C.

Unfortunately, I can not use Primus because it's a public parking lot (while it works very well, people with pets, cars, wild animals are not safe from the fire, the domestic ones do not).

On a 1000W hob it took about 1/2 hours to warm the entire engine. The engine was hot and outside was 0C.
At 3000W the time is reduced to 10 '. Unfortunately, there is no possibility of starting in advance without direct supervision.
A device exists if it is provided with limitation and safety features.
As soon as you get to the car, it is warm enough for a normal start.

[tolsen]

Bitumen is made from oil so normal engine temperature is no problem except when exposed to heat from Primus.

[mottofreee]

The bitumen soaks at 50-60 degrees, I think it's coming short. Coming with glass fiber or something will stay there.
From the oil sump
Is there any thermal insulator being liquid?
Primus method is inapplicable in my case.

[tolsen]

There are lots of second hand Webasto heaters on eBay. Some are rather cheap. Can’t be that hard to plumb one in. Assume they fit under the car next to fuel tank.