Thoughts on cooling a model engine with oil instead of water

[xander janssen]

Hi,

In order to reduce potential issues with corrosion due to various materials (aluminium, steel, brass), I was thinking on using oil instead of water/glycol to cool my model engine.

According to Wikipedia, there are advantages and drawbacks on using oil.

Wikipedia oil cooling

I my opinion, the drawbacks e.g. lower specific heat, can degrade at high temperature do not hold for a model engine.

How do you think about this?

Regards,

Xander

 

[Nerd1000]

I see no reason it cannot be done. Though I unsure what oil would be the best choice.

 

[danallen]

How about a soluble mix like we use for machining?

 

[michael.kilpatrick]

You could look into waterless coolant, I saw Edd China using it in one of the Wheeler Dealer programs.
Should have all the corrosion inhibitors as he mentioned it never needed changing.
Regards
Mike

 

[Nikhil Bhale]

In marine industry there are special "boilers" where oil is used instead of water, called thermal oil boilers. Heated oil at lower pressure and high temperature is used as a heat source for various processes.
I don't know which oil they use as a working fluid, but it can suit your purpose.

Regards
Nikhil

 

[Daryl_bee]

Hi,

In order to reduce potential issues with corrosion due to various materials (aluminium, steel, brass), I was thinking on using oil instead of water/glycol to cool my model engine.

According to Wikipedia, there are advantages and drawbacks on using oil.

Wikipedia oil cooling

I my opinion, the drawbacks e.g. lower specific heat, can degrade at high temperature do not hold for a model engine.

How do you think about this?

Regards,

Xander

Motorcycles have been doing it for a while

 

[aka9950202]

Motorcycles have been doing it for a while

Automaric transmissions use oil cooling. Some cars also cool the engine oil. The engines that have oil coolers also use water cooling as the main cooling system.

Cheers,

Andrew in Melbourne.

 

[Daryl_bee]

Hi,

In order to reduce potential issues with corrosion due to various materials (aluminium, steel, brass), I was thinking on using oil instead of water/glycol to cool my model engine.

According to Wikipedia, there are advantages and drawbacks on using oil.

Wikipedia oil cooling

I my opinion, the drawbacks e.g. lower specific heat, can degrade at high temperature do not hold for a model engine.

How do you think about this?

Regards,

Xander

Forgot to mention, the specific heat capacity of water at room temperature is 4181 J kg-1 K-1, and that of a typical oil is 2000 J kg-1 K-1 so oil is only approximately 50% as effective as water at cooling. That may be perfectly fine, or a problem, depending on the specifics of the design. Oil, as you state, does have it's other upsides.

 

[mrehmus]

Regular high-end antifreeze would work well and could be drained and reused.

 

[Nerd1000]

How about a soluble mix like we use for machining?

My concern with oil water emulsion would be the tendency for bacteria to grow in it if left for a long time. Though I have had some success preventing this by putting bits of copper scrap in the container.

 

[bluejets]

In order to reduce potential issues with corrosion due to various materials

That's why they use certain types of liquid coolant for many engines such as motorcycles, go-karts, aircraft, snow mobiles on and on.
Seems sufficient for them to use.
Why try to re-invent the wheel?

 

[minh-thanh]

Hi,

In order to reduce potential issues with corrosion due to various materials (aluminium, steel, brass), I was thinking on using oil instead of water/glycol to cool my model engine.

According to Wikipedia, there are advantages and drawbacks on using oil.

Wikipedia oil cooling

I my opinion, the drawbacks e.g. lower specific heat, can degrade at high temperature do not hold for a model engine.

How do you think about this?

Regards,

Xander

Hi Xander .
I have used oil as a coolant a few times when the water cooling system was not finished, more oil in the crankcase, a little oil in the water jacket , they are quite effective with home engines.
If I let the engine run a little longer, the oil will heat up and there will be some white smoke.

Why try to re-invent the wheel?

Because simply this is a home engine forum
Because he values the achievements he has made
Give your opinions, should or should not, good or not, advice ,..., Don't give stupid opinions

 

[TonyM]

Motorcycles have been doing it for a while

The various glycols used are pretty toxic, some more than others so not really suitable unless it is an enclosed system.

 

[GreenTwin]

I noticed in one of the old Baker Ball Hopper Monitor factory brochures that they mention using oil in lieu of water in the water hopper, to avoid the dreaded frozen and cracked water hopper casting.

As I recall, using oil in the water hopper was only good for about 1/4 load.

Oil also tends to be very messy, and tends to get everywhere in an open system.
Cooking oil would be environmentally friendly, and they use some derivative of vegtable oils as a less-flamable alternative in power distribution transformers, if you specify it that way.

.

 

[Hopper]

The cooling in an open hopper engine comes from the latent heat absorbed when the water changes state to a vapor and boils off. The water in the hopper can not go above a nominal 212 degrees F.

Oil will boil at a higher temperature so the engine will run hotter. And it gets smoky and spitty and messy and could be a fire hazard. So I would not use oil in an open hopper cooling system.

But in a radiator system oil could work ok, as certain motorcycles have done. Then again, why not use readily available pre-mixed automotive coolant in a contained system on a model? It has all the corrosion inhibitors and can be left in the engine/radiator for up to 8 years with the latest longlife red coolant varieties.
And it comes in one quart "top up" bottles just right for model use.

But I would not use auto coolant in a hopper engine either, because it boils at a higher temperature so will run the engine hot.

 

[Richard Hed]

That's why they use certain types of liquid coolant for many engines such as motorcycles, go-karts, aircraft, snow mobiles on and on.
Seems sufficient for them to use.
Why try to re-invent the wheel?

As I said in another post, I haver some square wheels to sell. Anyone interested?

 

[Steamchick]

I would use a regular automotive coolant at 50% mix because I knew all about it - corrosion protection etc - From my job in Engine Design .
But in a hopper system relying on latent heat removal of engine heat and the temperature control of water at 100degC., I agree that is unsuitable. But so is oil! Changing the boiling point changes the engine temperature on a boiling system (but NOT a recirculating ststem with heat exchanger. That relies on FLOW.).
In a recirculating system, you should use something like a 5W20 engine oil, that has low viscosity both cold and hot, but it will only carry away less than half the heat that water can. So you need more than double the flow you get with a standard water pump. E.g. A much bigger drive pulley to drive the water pump pulley! Can the belt a nd pulley be changed?
K2

 

[The Ignoble Troll]

I noticed in one of the old Baker Ball Hopper Monitor factory brochures that they mention using oil in lieu of water in the water hopper, to avoid the dreaded frozen and cracked water hopper casting.

As I recall, using oil in the water hopper was only good for about 1/4 load.

Oil also tends to be very messy, and tends to get everywhere in an open system.
Cooking oil would be environmentally friendly, and they use some derivative of vegtable oils as a less-flamable alternative in power distribution transformers, if you specify it that way.

.

They use veggie oil with friction additives in environmentally less unfriendly hydraulic oil.

 

[Richard Hed]

The nazis apparently used veggy oil but I don't know what kind. I do know the wrong kind will gu m up after a while

 

[The Ignoble Troll]

The nazis apparently used veggy oil but I don't know what kind. I do know the wrong kind will gu m up after a while

Rapeseed? It was used by all sides as a lubercant because it wets metal but was inedible due to it's acid content.

Some Canadian scientists used early gene manipulation and came up with CANada Low Acid oil or Canola which was edible and let those war time grease production fields become food production fields.