Using motor oil as a coolant... Thoughts?

I guess Henry didn't see that one coming...

 

What about the radiator hoses. I don't think they would last to long with oil in the system. Or am I wrong? I've seen hoses that soften up when there's been oil leaking on them for some time.

 

Well that's just a little different than what I got in the pits with the Suzuki guys. The oil cooling wasn't hype as long as the bike was stock. The problem as related to me was they weren't having problems with the production machines but with the superbikes and endurance bikes.. I got most of this from Keith Perry who was the Crew Chief for Team Suzuki Endurance, otherwise known then as Team Hammer. Now this was right before then after the changeover from oil to water. One of the biggest problems seemed to be the lack of adequate cooling fins. See attached pic. You can see the substantial air cooled fins vs. the "well they're fins" on the oil/air cooled bike. For the GSXR to do as well as it did as well as it did if the cooling didn't work is pretty damn good.

 

By "Hype" what I meant was that it wasn't really "Oil cooled" per se but that the oil cooling was just a component in the overall cooling effect. I did not mean to imply that it didn't work, actually worked quite well for it's intended purpose. They hype was the use of "Oil Cooled" and the way it was presented to the public to make us believe that it was as good or better than water cooling, that's all.

 

Found this to be an interesting related link.

http://www.engineeringtoolbox.com/specific-heat-fluids-d_151.html

 

Just about every auto transmission ever made is oil cooled including some that weigh more than your average car and transfer hundreds of HP. Some have water to oil heat exchangers and some are air to oil but they still run in the 220-230 range.An automotive engine can run comfortably at that temperature. Problems with overheating with water/antifreeze are not caused by to much heat in the engine but rather the mix boiling away from the iron causing hot spots. Oil with a boiling point of approx 350 would be less inclined to do this.
Case in point- A Allison TG 3spd that will handle 350 Diesel Hp will run comfortably at a 100 dg ambient air temp with 25gallons of 5w hydraulic fluid and a four tube oil to air cooler that measures 10x 20 inches. They also work fine from cold start at Odg with no changes.
Now how does all this apply to a IC engine? I am not sure but I believe that a oil cooled one would work just fine given the right capacity of fluid and cooling capacity. A More positive type of coolant pump would probably be required but not necessarily.
As long as the cooling system was intact, I don't believe that the oil would ever have to be changed as corrosion would not happen as there would be no corroision inhibitors to be lost as in antifreeze. A sealed expansion chamber would prevent the contamination with dirt as happens in cars with a recovery system. Oil is not condusive to electrolisys so you wouldn't have the dissimilar metals problem.
That all brings us full circle back to Granddad Baades 2 cylinder 10 hp hit and miss Mc Cormick irrigation pump circa 1902 that was cooled by about 10 gallons of oil in a resevoir that surrounded the cylinders.
So why do we use antifreeze? Don't know but I would bet that there is money involved.

 

I ran motor oil through the radiators of all three VWs I owned.

 

from personal experience racing both types of suzuki bike motors, you are both correct. Most people considered the "oil cooling" on the 92 and earlier bikes to be air/oil cooled. there was no cooling around the cylinder (just the cooling fins for air flow), just the oil sprayed onto the piston bottoms. This cooling system was adequate for the bike and it's intended street usage. When you pushed it any harder than stock you had the hardest time keeping it cool. and this is the main reason you won't find oil cooled motors gaining favor.

it takes HUGE volume of oil to cool the motor. so it takes forever to get the oil up to temp. cold oil means drag!

normal oil temps run between 280-360 degrees. so that helps off set the thermal inefficiency of oil verse. water. the greater the difference between your coolant and the air the more efficient. The problem is it takes longer to get the oil up to temp.

my gsxr would run 120+ psi of oil pressure cold. I'd come in after a race and it would be 0-5lbs at idle.

by the third year I ran an air/oil cooled motor (92 gsxr 750 in a minisprint) I was running three seperate oil coolers one of which was out of a helicopter that had a thermostat in it. this was a "stock" cl*** that only allowed blueprinting to within factory specs. rev limiter at 12.5k and never go below 10k for the entire race.

 

I dont think the ****** comparison is a fair one. I read somewhere that the heat in a ****** comes 70% from the engine it's bolted to, 25% from the torque converter, and only 5% from internal friction. Dont know if that's true or not, but I seem to remember it that way. The ****** only needs to vent the heat it picks up, while an engine, that's continuously burning fuel, is producing heat that needs to be disapated.

As to money being involved, modern antifreeze didn't even come on the market untill the 50's.

I'm wondering why Henry Ford and Walter P. Chrysler didn't explore this avenue back when all they produced were bangers.

Oh, and to add to the list of cars notorious for head gasket problems, the FWD V8 caddy [aluminum block, iron heads ], the 429-460 fords, and ANYTHING that ever rolled off a Peugeot ***embly line

 

Truck with large radiator and huge grill opening.
Winter.
SBC.
Still some water/coolant in system to thin.
Engine was probably still somewhat warm when filled.

I think you could have put crisco in it and driven it home. Probably not too far off the BS factor in my mind.

 

I'v still got 2 VW bug radiators in stock, along with 4 upper radiator hoses from a Corvair, 3 complete sets of muffler bearings, 4 quarts of blinker fluid, a knutsen valve, and a set of headlight warmers to fit a 70's model Plymouth if your interested.

Been sitting on these damn obsolete parts for years... I'll make you a great package deal..... Interested?

 

The link listing the specific heat capacity of various fluids also says that water is a better coolant than oil. It says it takes over twice as much energy to raise a kg of water one degree as it does oil. So, not only is water a better heat conductor, it's a better heat absorber. Seems pretty clear why early car makers chose it. Especially since it was practically free.

 

and if a hose blows its easier to clean up water

 

If it's a well tuned plain worn SBC the thermal conductivity isn't even an issue i've ran my beater with less that a half gallon of water on occasion at 60-70 and never siezed it, or atleast because of that

 

I had a water-cooled machine at work that continually had corrosion problems inside from the process cooling water. As an experiment, I converted it over to use oil instead of water as a coolant to see if it would work like that to get rid of the corrosion problems. I used a separate pump to pump the oil and ran the oil through a heat exchanger so that the water cooled the oil, and the oil cooled the machine. I had a vented oil tank on the exhaust side so that no pressure would build up in the closed loop, and the oil continually circulated. The temperature crept up a lot higher in certain places than what it did with the water as a coolant, but it turned out the main reason was that the air bubbles in the system wouldn't dissolve into the oil. There were pockets full of air where the oil couldn't cool anything.

With water, the air can dissolve into it (or mix easily as a fizz of fine bubbles?) and the bubbles eventually work their way out of the system. With oil, you can get pockets of air that just never leave. So that's probably one reason that it doesn't work all that well as a coolant in an engine. It did work fine otherwise in my machine at work, except for those small areas where I couldn't get the air pockets out, where things would overheat.

 

all I have to say is Porsche. 3 1/2 gallon oil chane in a p*** car that is oil cooled. IT could be done, i belive it worked, im sorry for the guy who had to clean that *** mess up after the head gasket job.