- February 3, 2013
- Posted by: Jeff White
- Category: Articles
There is certainly a lot that goes into ‘winterizing’ your heavy trucks in order to keep them in top working order during the cold months. Draining your air tanks is a very important part of truck maintenance because it helps to prevent freezing in your air lines and all of your valves. Once you have freezing in your air lines or your valves, it causes your air not to build up, costing you money for towing and could be costly situation.
No amount of truck maintenance can make up for the amount of hours put on your engine when idling, so it is important to remember that you should try not to allow a heavy truck to idle during the winter months, unless absolutely necessary. This practice being hard on the engine—particularly during the cold season—it can also cause the discharge lines to freeze up and cause the compressor to fail. Therefore, before draining air tanks in heavy trucks, it is important to understand the tips for handling discharge lines as part of routine truck maintenance; this is especially true when long periods of idling are unavoidable.
Handling Discharge Lines
If discharge lines are not included in routine truck maintenance, it could cause serious issues with air brake systems. It is important to follow these guidelines during the winter months, especially if drivers are on routes that force them to idle for long periods of time. First, it is important to ensure that the discharge line itself is free from any kinks or water traps and that it is always sloping downward from the compressor discharge port. Next, if it is necessary to cross the lines over the frame rail at any point, these crossovers should be located as close to the compressor as possible. Also, be sure that lengths and diameters of the lines are correct for the vehicle. This is proper discharge line truck maintenance.
Draining Air Tanks
It is necessary to drain air tanks regularly as a part of routine truck maintenance on heavy trucks, even if your truck has an air dryer. Air dryer do help prevent water in the system, however, some trucks produce a lot of water in their systems. Any of the reservoirs in a brake system can accumulate moisture, and this moisture can turn to ice when it gets cold or below freezing outside. Before the cold season arrives, it is important to check the brake system for excessive leaking; if there is a lot of leakage, the system will pump in even more air and moisture that what is typical. Aside from water and air, it may also cause contaminants to accumulate, and this can hinder the performance of the air brakes. This truck maintenance step is critical for ensuring that brakes continue to operate properly and for preventing damage.
How to Drain Tanks
The absolute best way to drain these air tanks as part of wintertime truck maintenance, especially if there is no air dryer, is to drain all of them on a daily basis. To do this, you should turn the engine off and drain all the air by opening the cocks. In fact, the best practice is to leave the cocks open overnight so that all of the air and contaminants are completely drained by morning. If there are automatic drain valves installed, this will eliminate the need to drain the tanks daily, but you will still need to perform manual draining on occasion as part of basic cold weather truck maintenance.
Alcohol Evaporator and Injection Systems
The processes for truck maintenance on vehicles that have alcohol evaporators and injection systems are a bit different. Before adding alcohol, it is important to first drain all of the air and moisture from the evaporator to ensure that there is no contamination. Next, add methanol alcohol to the system as per the vehicle’s manual, and keep a close eye on the alcohol consumption for a few days. Normal consumption should not exceed between one and two ounces of alcohol per hour. Other forms of truck maintenance will need to be performed if consumption is greater than this. Trucks that operate in stop-and-start situations will consume more alcohol than vehicles that are used solely on the highway.
Other Truck Maintenance Tips
There are other tips for air brake maintenance that should be observed along with proper air tank drainage for the best performance possible. Some of these include knowing how to thaw out frozen tanks and lines; only do so in a warmed building so that the integrity of the lines is not compromised with excessive heat. Never introduce flame to the lines as this can result in a fire or explosion. Finally, it is important to check the operation of automatic drain valves regularly. Cold weather truck maintenance is very important and can save time, money and even prevent injury.
Draining air tanks in cold weather months is one of the most important and often simplest forms of truck maintenance. Depending on the type of system you have and the type of weather you expect, the methods for draining these tanks and lines may differ depending on what truck you have.
Once your line are frozen and ice has built up there are two choices you have to remove the ice. One is to run alcohol into the main compressor line that pushes the air through your system, or put your truck in a warm place until moisture has thawed, allowing you to drain the system. Not always will the alcohol work, this will, depend on how much ice buildup you have in your lines.
The only safe way, to know you will not freeze up is to always make a habit of draining your tanks.