Doosan DX85R Excavator: Swing Motor Dipstick and Maintenance Insights

[MikePhua]

The Doosan DX85R is a robust and reliable compact excavator, ideal for a variety of construction and landscaping tasks. It is known for its efficiency, compact size, and powerful performance. However, like all heavy machinery, it requires regular maintenance and troubleshooting to keep running smoothly. One common issue that operators encounter is with the swing motor dipstick, which is crucial for checking the hydraulic oil level of the swing motor.
In this article, we will explore the importance of the swing motor dipstick in the Doosan DX85R, how to properly maintain the swing motor, and common problems associated with it. Additionally, we will discuss the role of hydraulic systems in excavators and provide practical tips for troubleshooting.
Understanding the Swing Motor in Excavators
The swing motor is an essential component of an excavator's rotation system, allowing the upper part of the machine (the superstructure) to rotate independently of the undercarriage. It is powered by the machine's hydraulic system, which delivers high-pressure fluid to the motor, enabling smooth and precise rotation. The swing motor works in tandem with other components, such as the swing drive and reduction gear, to provide full 360-degree rotation.
The swing motor is lubricated and powered by hydraulic oil, which is stored in a reservoir and pumped through the motor to maintain its functionality. Over time, the hydraulic fluid level can drop due to leakage or contamination, which can negatively impact the motor's performance and cause overheating or mechanical failure.
The Role of the Dipstick in Swing Motor Maintenance
The dipstick serves as a simple tool for checking the hydraulic oil level in the swing motor. By inserting the dipstick into the motor's oil reservoir, operators can determine if the fluid level is sufficient. This is important for ensuring proper lubrication and efficient operation of the swing motor.
If the oil level is too low, the motor may struggle to rotate, experience excess wear, or even suffer from internal damage. Conversely, if the oil is overfilled, it can cause pressure build-up and increase the risk of leakage or overheating. Regularly checking the oil level with the dipstick is a quick and effective way to maintain the health of the swing motor.
How to Check the Swing Motor Oil Level
Properly checking the swing motor oil level is essential for the smooth operation of the Doosan DX85R excavator. Here’s a step-by-step guide to ensure you're checking it correctly:

1. Locate the Dipstick:
   The dipstick is usually located near the swing motor on the machine's upper structure. It is typically marked with a bright color (such as yellow or red) for easy identification. Refer to your operator’s manual for the exact location of the dipstick on your specific model.
   
2. Turn Off the Engine:
   Before checking the oil level, ensure that the excavator’s engine is turned off. This ensures that the hydraulic fluid settles, providing an accurate reading of the fluid level.
   
3. Clean the Dipstick:
   Pull out the dipstick, and wipe it clean with a lint-free cloth to remove any oil residue. This prevents dirt and debris from contaminating the oil when the dipstick is reinserted.
   
4. Reinsert the Dipstick:
   After cleaning, insert the dipstick fully back into its tube to ensure an accurate reading. Let it sit for a few seconds to allow any excess fluid to drain from the dipstick tube.
   
5. Check the Fluid Level:
   Pull the dipstick back out and examine the oil level. The dipstick will usually have two marks indicating the minimum and maximum oil levels. If the oil level falls below the minimum mark, it’s time to top up the fluid. If the oil level exceeds the maximum mark, excess fluid should be drained.
   
6. Top Up or Drain Oil if Necessary:
   If the oil is low, add the recommended hydraulic fluid. Be sure to use the correct type and grade of fluid as specified in the operator’s manual. If there is too much oil, use a siphon or drain plug to remove the excess.
   

Common Problems with the Swing Motor and Solutions
While the swing motor is designed to be durable, several common issues can arise due to improper maintenance, wear, or contamination of hydraulic fluid. Below are some of the typical problems operators may encounter and how to address them:

1. Low Swing Motor Power
   • Cause: Low hydraulic oil levels, air in the system, or clogged filters.
     
   • Solution: Check the oil level using the dipstick and refill if necessary. Bleed the hydraulic system to remove any trapped air, and replace the hydraulic filters if they appear dirty or clogged.
     
2. Erratic Swing Movement
   • Cause: Contaminated or degraded hydraulic fluid, faulty valves, or air in the hydraulic lines.
     
   • Solution: Replace the hydraulic fluid if it appears dirty or discolored. Inspect and clean the valves and hoses to ensure they are free from debris. Bleed the system to remove air pockets.
     
3. Overheating of Swing Motor
   • Cause: Insufficient oil levels, overfilled oil reservoir, or poor circulation due to blocked filters.
     
   • Solution: Check the oil level and ensure it’s within the proper range. Clean or replace the hydraulic filters and check the fluid for contamination. Ensure the motor's cooling system is working efficiently.
     
4. Leaks Around the Swing Motor
   • Cause: Worn seals, gaskets, or loose fittings.
     
   • Solution: Inspect the seals and gaskets for wear and replace them if necessary. Tighten any loose fittings and check for signs of damage or cracks in the motor housing.
     
5. Unusual Noises from the Swing Motor
   • Cause: Lack of lubrication, worn-out bearings, or contamination in the hydraulic fluid.
     
   • Solution: Ensure that the oil level is adequate and that the fluid is clean. Inspect the bearings and replace them if they are damaged or worn out. If necessary, drain and replace the hydraulic fluid.
     

The Importance of Regular Maintenance
Routine maintenance and timely checks of the swing motor dipstick are essential for preventing breakdowns and extending the lifespan of the Doosan DX85R excavator. By regularly checking the oil level and addressing potential issues before they escalate, operators can avoid costly repairs and keep their equipment running smoothly.
In addition to swing motor maintenance, it’s important to monitor other key systems on the excavator, including the engine, tracks, and hydraulic pumps. A comprehensive maintenance schedule that includes regular oil changes, filter replacements, and system inspections will ensure optimal performance and reduce downtime.
Conclusion
The Doosan DX85R is a powerful and reliable compact excavator designed to handle demanding tasks with precision and efficiency. Regular maintenance of the swing motor, including checking the oil level with the dipstick, is crucial for ensuring the longevity and optimal performance of the machine. By understanding the common issues associated with the swing motor and implementing proper maintenance practices, operators can maximize the excavator’s efficiency, reduce operating costs, and extend its service life.