It’s always a good idea to follow best practices in any maintenance program. But what about avoiding worst practices?
Here are some common mistakes construction equipment fleet managers make regarding lubes, coolants and greases. Global Heavy Machinery Parts Dealers: AGA Parts.
Coolants can be the most commonly mishandled part of a fluid management program, since experts say they are the least understood. Unfortunately this lack of understanding can have catastrophic impacts and cost a lot of money.
All coolants are not alike nor interchangeable. There are two distinctly different types of coolant – older conventional fully formulated and the newer extended life (or organic acid technology or OAT). These two coolants protect engines from corrosion in different ways, and anytime you mix the two, you dilute or reduce their effectiveness.
The problem arises when someone tops off a radiator with the wrong fluid. Maybe the maintenance manager uses the right coolant. But does the operator, the field service guy, a contracted service provider, a driver or whoever first notices the low coolant level know this?
The different additives in those different coolant chemistries don’t help each other out. In mixing the two, you are setting yourself up for possible catastrophic corrosion – such as corrosion that eats a hole from the coolant side of a cylinder liner to the oil side. And by the time you see coolant show up in your oil samples, it’s too late. The major damage has been done.
The solution is to make sure everybody – mechanics, operators, drivers, contract maintenance people – understands the brand and type of coolant used and the dangers of mixing two formulas. This requires training and perhaps an operator care program, and it should be your first line of defense.
The second line of defense is to monitor coolants with test strips made for your coolant type. Wet these simple paper strips with coolant in the system. If they turn one color, you’re good to go. A different color means your coolant doesn’t have a high enough percentage of the right additives to prevent corrosion.
Another recommended step is to check the freeze point of the coolant with a hygrometer, or for more accurate results, a refractometer. This will tell you if your coolant is too diluted with water, which also reduces its anti-corrosion properties.
If the coolant is out of spec, it’s not usually necessary to drain and refill the entire system, which on some machines can require dozens of gallons. Coolant vendors offer concentrated coolants to allow customers to bring the coolant levels to the recommended freeze points. A freeze point correction chart will show you how to adjust your coolant so that it is at the proper level. Correction fluids are used to restore additive content to recommended levels. These two procedures enable you to bring your equipment’s coolant back into spec without draining the cooling system.
Your coolant vendor can help you establish these procedures. A good practice is to check the coolant every time you change the oil.