Engine Oil Drainage on the Volvo MC85C and the Myth of the Missing Tool

[MikePhua]

The MC85C and Volvo’s Compact Loader Line
The Volvo MC85C skid steer loader was introduced as part of Volvo Construction Equipment’s compact loader series aimed at urban contractors, landscapers, and utility crews. With a rated operating capacity of around 1,850 lbs and a 74 HP diesel engine, the MC85C was designed for maneuverability and service accessibility. Volvo’s emphasis on operator comfort and maintenance simplicity made the MC85C a popular choice in North America and Europe, though its service procedures occasionally spark confusion—especially around engine oil changes.
The Drain Plug Dilemma and Tool Misconceptions
One of the most persistent myths surrounding the MC85C is the belief that a “special tool” is required to drain the engine oil. This misconception likely stems from the plug’s recessed location and the lack of clear documentation in some service manuals. In reality, the oil drain plug is accessible with standard tools, though it may require a low-profile socket or extension depending on the machine’s frame configuration.
Operators often mistake the plug for a sensor or hydraulic fitting due to its proximity to other components. The plug is typically located beneath the engine block, near the skid plate, and may be shielded by a protective bracket. Removing this bracket reveals the drain point, which accepts a standard 3/8" or 1/2" drive socket.
Recommended Tools and Setup
To perform an oil change on the MC85C, the following tools are recommended:

• Low-profile oil drain pan (minimum 2-gallon capacity)
  
• 3/8" drive ratchet with extension
  
• 17mm or 19mm socket (depending on plug size)
  
• Torque wrench for reinstallation
  
• Funnel and clean rags
  
• OEM oil filter and 2.5–3 gallons of 15W-40 diesel-rated engine oil
  

Some operators prefer using a vacuum extractor for cleaner removal, especially in tight shop environments. However, traditional gravity drainage remains the most thorough method for removing sludge and contaminants.
Oil Change Procedure and Best Practices
The oil change process should be performed with the engine warm but not hot. Warm oil flows more freely and carries suspended particles out of the sump. The steps include:

• Park the machine on level ground and engage the parking brake
  
• Remove the engine access panel and locate the drain plug
  
• Position the drain pan and loosen the plug slowly to avoid splashing
  
• Allow oil to drain completely (10–15 minutes)
  
• Remove and replace the oil filter, lubricating the gasket with fresh oil
  
• Reinstall the drain plug and torque to spec (typically 30–35 ft-lbs)
  
• Refill with fresh oil and check the dipstick
  
• Start the engine and run for 2 minutes, then recheck oil level
  

Always dispose of used oil and filters according to local environmental regulations. Many shops use sealed drums and scheduled pickups to comply with waste management laws.
Common Mistakes and Troubleshooting
Several issues can arise during an oil change:

• Over-tightening the drain plug, leading to stripped threads
  
• Forgetting to remove the old filter gasket, causing double-seal leaks
  
• Using incorrect oil viscosity, especially in cold climates
  
• Failing to prime the new filter, resulting in delayed oil pressure
  

To avoid these problems, operators should follow manufacturer specs and use high-quality filters. Volvo recommends filters with anti-drainback valves and high burst pressure ratings to withstand cold starts and high RPM operation.
Service Intervals and Oil Analysis
Volvo recommends changing engine oil every 250 hours under normal conditions, or every 100 hours in severe-duty applications (dust, heat, heavy load). For fleets, oil analysis can extend intervals by identifying wear metals, fuel dilution, and viscosity breakdown. Sampling kits are available from most dealers and provide lab results within 48 hours.
One contractor reported extending oil changes to 400 hours after consistent lab results showed minimal degradation. However, this practice should only be adopted with verified data and proper filtration.
Conclusion
Changing engine oil on the Volvo MC85C is a straightforward task once the drain plug is located and the tool myth dispelled. With the right setup, clean technique, and adherence to service intervals, operators can keep their machines running smoothly and avoid costly engine repairs.
In compact loaders, oil isn’t just a fluid—it’s a lifeline. And knowing where to drain it is the first step in keeping that lifeline clean.