Continuing the series of service guides, which aim to help in the proper preparation of construction machinery for winter, we once again present our service, this time for the Liebherr A314 wheel excavator.
What breaks in hydraulics in winter - how to protect pumps and other hydraulic components from frost?
We start, as always, with changing the filters and it might seem that everything has already been said and written about this. However, despite this, one can still encounter a rather indifferent approach to this issue. By adhering to the manufacturer's recommended intervals for changing hydraulic filters, you can protect yourself from a serious failure of the entire system.
Why is this so important? Let's imagine a situation where all the chips and impurities accumulated in the bypass valves, in the hydraulic filter are moved to the pump and further through the pipes to the entire hydraulic system. It doesn't take much imagination to realize what this can lead to. Often, the poor condition of the hydraulic pump is directly caused by neglecting the issue of regular filter replacement.
To the common mistakes made during the operation of the machine, let's add occasional topping up of hydraulic oil. This is not the best practice because the hydraulic oil present in our machine may have completely different quality parameters than the one being topped up. Mixing oils can cause a decrease in the performance of hydraulic components in construction machinery.
The best practice is to regularly check the level and quality of hydraulic oil and to carry out its full replacement according to the schedule recommended by the machine manufacturer. Another way to extend the life of hydraulic oil is to filter it - you can read about the whole process in this article.
Let's also take care of the engine of our machine
Let's start by checking the condition of the engine oil, so we pull out the dipstick, wipe it with a cloth and put it back in. We check what the oil level is on the dipstick - it should be between the "MIN" and "MAX" markers. It is also worth paying attention to the condition of the fluid in the cooling system of the construction machine's internal combustion engine. In the face of the upcoming frosts, we can check the freezing temperature of this fluid.
This is important because frozen coolant can cause serious damage to the engine - even to the point of bursting the radiator. Measuring the freezing temperature is not a big problem and can be done with a cheap and easy-to-use tester. In essence, we are checking the density of the liquid itself, as it determines the freezing temperature. Remember to check the liquid when the engine is cold, otherwise we risk burning ourselves.
We can also find out what the situation is with the fuel system, specifically, whether there is water in it. Contaminated fuel reduces combustion efficiency, which can lead to a decrease in machine power. The device responsible for removing water from the fuel system of a construction machine is a water separator.
Thanks to the filter inside, water is separated and collected in a collection chamber at the bottom of the separator. In newer models of construction machines, we can find an indicator that clearly shows the water filtered out of the fuel. In this way, we can find out if everything is working properly, if the liquid in the separator seems to be contaminated and thick, you need to consult the service.
Staying with the fuel, we would like to point out that if we decide to change the fuel for winter, it is better to fill it up completely, rather than use additives, which are half measures, whose effectiveness may be significantly lower than the parameters of typical fuel intended for use in frosty weather.
This is important because diesel oil contains paraffin compounds, which begin to crystallize at low temperatures as part of a natural process, but the larger particles formed in this way can deposit in the fuel filter, blocking its flow, which can ultimately lead to problems with starting the construction machine. Especially summer fuel is susceptible to this type of circumstance, as it is not adapted to low temperatures and therefore it is recommended to replace it with fuel resistant to paraffin crystallization. The aforementioned additives may be insufficient and it is better not to risk.
What else can we protect before winter?
It is obvious to check the battery, in winter conditions it is necessary to take care of its full charge and insulation, so that the machine works properly. Machines with a central lubrication system should also be checked in this respect - we are talking about the quality of the grease. In winter, the days are shorter and it gets dark faster, so we emphasize not to neglect lighting - working headlights, warning signals and other lighting elements should be fully functional.
