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Can you use motor oil for a liquid cooled computer? Answered

I would love to tell my friends that my computer uses car oil to keep it cool. I would probably use SAE 5-10 oil with a SA or SB rating.


I doubt the manufacturers actually check for mineral oil compatibility for their circuit boards, wires or components. This could be a very bad idea. Oh sure, there are instructables, but see if they can boast say two or three years stable operation before trying it.

THE material for immersion cooling of course is Fluor-inert, but that's hideously, hideously expensive.

Good though.


One of the Universities I went to had a picture of a mouse immersed in fluorocarbon. And another showing the same (I guess) in the hand of a happy-beardy, I guess as illustration that the stuff is breathable id oxygen-saturated.


OK, I'll bite...what the heck is a "happy beardy"? A smiling professor?

Yes, beards were quite fashionable amongst Academics in the past, and possibly still are...
Yep, Samuel Danishefsky:


lol...but it's a real slang in the UK? Or just a lemonism?

"Beardy-wierdy" is UK slang, I may have contracted it to a Lemonism.
My old Tutor:


He looks like a beared weirdo to me ;-)

thanks for the explanation. I figured it must be a UK slang but wanted to make sure.

Hmm... maybe I ought to name a band that...we could play Grateful Dead music... punk style

Look up "Liquid breathing" We watched The Abyss last week, and liquid breathing is a major plot device. I was surprised years ago to find its a theoretical possibility !

The problem is to do with the dissolvability of CO2 and the volumes of liquid you have to respire - any kind of effort and you're stuffed.


Okay, here is what you need! A Pump, for light weight oil, liquid blocks to attache to your CPU, GPU, board BIOS Chip, Hard Drives, memory SIMMs and power supply transistors, oil cooler and as many fans as you can place on both sides of the cooler, (both pushing air through and pulling air from the cooler!) and a reservoir (About a quart or more.
There are many good oil coolers that are quite small. The Hayden Wafer type is the most efficient ands looks really cool (No pun intended!). Plumb the many cooling blocks in pairs of series connections. Connect the SIMM coolers to one branch, the CPU and GPU to another, the Power supply and hard drive to another and then what ever else. MOTOR oil and mineral oil is too thick and won't flow well. But Transmission fluid is just the ticket and it is for a higher temperature anyway. Your typical gas engine does not run hotter than 205 to 210 degrees but your transmission runs as high as 250 degrees all the time! The use of Silicone based hoses it recommended, butyle rubber will deteriorate quickly. CLEAR silicone hose is available and with red of blue transmission fluid (Dexron 2 or Dexron 3 or Dexron Synthetic) should look pretty cool as well. If you do High Tech and use 'O' ring sealed, DOT approved, quick connect fittings, you'll greatly reduce the possibility of leaks. The DOT approved connectors are best because they use a metal insert (Made of stainless steel!) that supports the hose from the inside to prevent the hose from collapsing and popping out of the fitting!

It is easy for people to say, "You can't do that!" What you have to remember is this, "You can't do that!" translates into, "I don't know how so why should you even try!" Well! When I added my transmission cooler to my truck it dropped the temperature almost twenty degrees. That change and converting to Synthetic Fluid made a huge difference in the performance of my truck. I pull a four ton trailer every where as part opf my mobile repair business and now, I do so without concern! The truck has 95,000 miles now and I sevice it religeously and have yet to see a break down. The engine and transmission never over-heat and I live in California where it can get real hot during the summer. At 92,000 miles I put a fresh water pump in the truck. I consider that a normal 'wear and tear' item! OH! And I just put on a second set of tires as well. The truck is fully equipped and I use the A/C all the time. So I think the small modification I made has paid for itself many times over! OH! And I use Synthetic Lubricants, exclusively, (Amsoil) in everything, Wheel Bearings, Rear Diff, Engine, Transmission! And a Synthetic Cetane Booster in the diesel fuel protects the injection pump. I tell you all this to let you know all this is not just coming off the top of my head. I am the person who makes it work, gets it down and there's a wrong way, the right way and MY way to do everything! MY way gets it done with improvments so it doesn't need 'doing' again too soon!

I think your idea, to cool a Computer with oil, is bold. I've seen it done with the computer SUBMERGED in motor oil, but the computer was glitchy and some of the chips did not get cool enough. Evident by the fact that after an hour of running the oil was a great deal wrmer than when it was first turned on! I think if that person had placed the computer in WD40 and pumped the oil through a cooler in a small Fridge, THAT would have been much better. Also, he should have used a SSD hard drive. The motor oil soon ate through the seal, around the hard drive, and it failed.

There are plenty of VWs that do not use water to cool them down. these use the oil and air. These VolksWagens have been around for many years 50 plus and you can still see them on the streets. Also Oil has higher thermal conductivity than air and unlike water oil does not conduct electricity. Also if water were to get into the container it would sit at the bottom as most  oils are less dense than water. Then there is also the fact that oil does not cause condensation problems like water cooling. I would recommend looking for motor oil that does not contain detergents. I would also choose a single weight motor oil. as it will consist of more of the same oil molecules as apposed to  oils that say SAE number W Number. You may want to look into what the motor oil has in it besides oil as some contain other additives besides what I have mentioned. there is something added to most oils besides detergents that could cause problems as it is meant to form a protective coating on the valves of cars to prevent ware. sorry but i cant remember what this additive is.  I have been doing research on this because i am planing to submerge two transformers for an arc welder I made to increase the duty time. Basically increase how long i can weld for. There are many devices that are oil cooled. you could also look into transformers like the ones you see hanging  form telephone poles as these often contain oil to help cool the transformers.  There is also a server company that has been experimenting with cooling computer servers with motor oil. Hope I was helpful.

P.S.I hate all the people who discourage people form trying things and don't know anything on the topic. If you have something to say just state the facts in an instructional manner don't say it wont work. and just because people say it wont work doesn't mean you shouldn't try. without people breaking the norms weo would never advance technologically. Where do you think we would be if no one tried for the unknown. things like the space exploration wouldn't exist.

If you did a web search on "computer oil cooling" you'd find the first link will probably be to Puget Systems http://www.pugetsystems.com/submerged.php
They feature 2 oil cooled systems, one built in 2007 and one built in 2008, both are still running (as of 2009).  They use mineral oil in a fish tank.  Idle temperatures stay under 40C.  Load temps get hot, 88C, but it takes 12 hours to reach that temperature.  Pumping the oil through a fanless radiator stabilized temps at 45C.  Although oil does not transfer heat as efficiently as water, water can only remove heat from small specific spots. Total immersion in the oil offsets the heat transfer disadvantage.
 - cheaper than water cooling
 - very quiet
- heavy
- messy
- hard drives, optical drives must remain outside (ssd drives can be submerged)
- wires cannot run directly out of the oil or oil will wick down the wire. A plug must be used where any wire comes out of the oil to break the wicking action.

Use good clean light paraffin - think Johnson's Baby Oil. Motor lubricants tend to contain additives which may possibly cause you (as yet unknown) problems.


SA oils do not have any additives.

What is SA? I know of SAE (Society of Automotive Engineers), but that I don't. Any sulphur content?


Oil's have a rating based on how many additives thay have. It goes from SA to SG. SA is pure oil, SG has lots of stuff.

Oil has a very poor thermal transfer coefficient, (about 1/3 that of water) so although one *could use it, imo, it would simply be a bold badge of stupidity, rather than a clever use of alternate materials..

In addition to it's high flammability, mess if any leaks are encountered, etc.

Sure you can.  Mineral oil would work fine.  Just look at this instructable.  I don't know how they are going to change memory or add a card etc. though.


8 years ago

You could, but oii just isn't efficient at heat gain or loss as is water thus not as good a medium for cooling. Plus there is one little property oil has that water doesn't, oil is flammable.

You might be able to make it work. I don't think it would be as effective as water cooling -- there are good reasons cars use water for that purpose.