NOTHING WILL shut down a producer's vehicle faster than an overheated engine. Failing to get the load of concrete to the jobsite on time is costly, but not as much as relining cylinders and milling cylinder heads, which could run up a tab of $12,000. And a new engine could top $30,000.
Engines are cooled three ways. Running at highway speeds with air passing around the block provides some, but most cooling comes from coolant and oil. Heat is absorbed by engine oil and carried to the sump and the oil cooler. That doesn't vary, unless you run out of oil.
Coolant, on the other hand, is under your control. Fully formulated coolant is a 50/50 mixture of ethylene glycol and water, with either supplemental coolant additives (SCAs) or long life coolant with organic acid technology (OAT) additives. To keep the coolant operating properly and to protect engine parts, SCAs or OAT must be checked and maintained periodically. Cooling system failures still cause a significant share of downtime.
Recently, non-aqueous glycol-based coolant has emerged as a maintenance-free alternative. So far, Evans Cooling Systems Inc. is the sole supplier. The waterless coolant provides adequate lubrication for water pumps. Because no water is in the coolant, there is no need to use additives to protect engines from its deleterious effects.
Water is an excellent heat transfer medium when liquid, but it changes state. When it boils at 212 degrees F, it creates vapor pockets that can insulate and hold heat in the metal rather than transferring heat away. When below 32 degrees F, water freezes, expands, and generates enough pressure to crack engine blocks.
Fully formulated coolant will prevent freezing to 34 below zero. It also raises the boiling point to 224 degrees F. Since engines operate at close to water's boiling point, the glycol adds a safety margin to prevent boil-over. Additional margin is provided by pressurizing the closed cooling system to one atmosphere (15 psi) above ambient. With the pressure cap, water boils at 250 degrees F and 50/50 coolant boils at 263 degrees F.
Freezing and boiling
Even without pressurization, Evans coolant won't freeze at 40 degrees F below zero. It boils above 375 degrees F, giving a huge safety margin. Water carries scale-forming minerals, but waterless coolant prevents scale buildup. It doesn't need a 15 psi radiator cap. Evans recommends keeping the same cap (it isn't necessary to change it). But the pressure will only build up to one to two psi. With no water to boil off, localized hot spots and mineral deposits are avoided.
Pitting is caused when bubbles form next to cylinder liners as they flex from the side thrust of pistons. When the bubbles implode, coolant impacts the outer walls of the liners with enough force to drill through. That lets coolant into cylinders and the oil sump.
SCAs form a protective coating that absorbs most of the impinging force. Without the protection, repeated implosions drill holes in the steel liners. Organic acids in long life coolants protect from pitting. With non-aqueous coolant, no water vaporizes and no bubbles form as the liners flex. The non-aqueous coolant quickly fills any voids. Since water is a corrosive agent, waterless coolant resists corrosion.
The antifreeze in Evans' non-aqueous coolant does contain ethylene glycol (EG), which is found in most conventional coolants. Traditional green EG antifreeze puddles found in parking lots and driveways are poisonous to pets and children attracted to glycol's sweet taste. Evans' blend is much less toxic and is safe for animals. If Evans' collant is ingested, no harm is done.