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Waterless coolant

Jay Leno uses this in his older cars that do not have a pressurized cooling system. It does not boil over and it does not corrode and it lasts the life of the vehicle. I don’t know about its toxicity if any, but it is expensive.

http://www.evanscooling.com/products/coolants/

Sounds way too good to be true. And at nearly $50/gallon, I’m not going to try it. But I guess Jay can afford it.

Jay Leno’s Big Dog Garage (a complex on industrial buildings) is loaded with cars from the past that are very different than today’s vehicles. And all are restored and routinely maintained by a staff of top-flight experts in antique cars. He even has a steam expert for his steam driven vehicles. I would recommend against making the assumption that the fluids Jay Leno uses in his collection have the lubricants and anticorrosives necessary for today’s engines, or are as good for your family car.

It’s also very possible that you don’t need to spend that much to protect your engine for life. In over 40 years of owning and maintaining cars (which includes draining and refilling the cooling system with fresh coolant occasionally) the only cooling problems I’ve had were due to a design defect ('72 Vega) and on a pickup with over 300,000 miles on it (the pump failed). Jay Leno is maintaining treasured antiques. I’m not.

Chemicals like these have been around for decades. Circulating temperature control systems in laboratories use them. The product is likely an alcohol or paraffin product. The vendor has to provide a MSDS, so you can see if there are any toxic ingredients.

I did a web search and NPG stands for Nonaqueous Propylene Glycol - an alcohol product. While Evans does not have a spot on their URL for MSDSs, they will email it to you if you ask for it.

He uses it in cars that do not have pressurized cooling systems. Does that sound like any NEW car?

A friend of mine uses this in his V8 powered S-10 pickup. It really works and was worth the $100 price because it no longer overheats. He can open the radiator cap on a hot day with the engine running because the stuff does not boil. I needed this kind of coolant back in my V8 Vega days. They were a blast to drive but every one of them that I ever owned overheated during the summer months.

The early Vegas overheated with the I-4 in them too…

If the boiling point is well above the operating temperature of the engine it would seem that heat transfer would be severely limited.

Propylene glycol boils at 370F at normal atmospheric pressure. It freezes at -74F.

Not obvious why it’d be a better coolant than normal 50/50 mix [edit - in the S-10], water has a higher heat capacity, I believe.

50/50 EG and water boils at 225F. That’s why it is used only in pressurized automotive coolant systems.

I’m wondering about using propylene glycol in the S-10, which could just as easily use 50/50.

I understand about using it in non-pressurized systems.

The EG/water mixture is much less expensive than the PG coolant. I’d just stick with what works. As long as the standard coolant does the job, why spend more?

One of the problems with NPG is that its specific heat capacity is not as high as a 50/50 mix of water/ethylene glychol. Therefore the hottest regions of the engine are going to run hotter. How hot is up to debate. NPG will resist nucleate boiling without system pressurization better than 50/50 mix.

Another problem with NPG is that all water has to be removed from the cooling system otherwise the benefits will not be attained. That means the entire engine and all its nooks and crannies and the heater system including the heater core(s) and valving has to be cleared of old coolant. If you should need an emergency radiator fill, you had better have some NPG along as regular service stations would not have it; most auto parts stores don’t carry it; and AAA would probably not have it one their service trucks.

NPG is great for flat head V8s that have power adders like superchargers, cams, high compression heads, etc. Since the stock engine has the exhaust passages traveling from inside of the V to the outside walls inside the block, a lot of head is added deep in the block before the coolant passes into the heads thereby into the outlet. If nucleate boiling occurs on the passages or exhaust valve seat area, a slurry of coolant and bubbles may pass from the block through the heads into the upper radiator tank before the bubbles condense. Foamed coolant does not conduct heat anywhere near as fully liquid coolant. Thus NPG helps “heater” engines survive.

texases…my friend use to run a 50/50 mix but the truck overheated. When he switched to the waterless coolant…no more overheating problems. He had to completely remove the water with the help of compressed air and let the cooling system dry out. He was skeptical just like I was but it worked. Like I said…I wished I had waterless coolant back when I ran V8 Vegas. It would have solved all of my overheating problems.