Replacing the Pump Fluid in the MS-40+ Rotary Vane Pump

Answer

This Information Applies To: Agilent 6000 Series LC/MS Systems equipped with MS40+ rotary vane pumps

Issue

Replacing the MS-40+ (rough pump) fluid periodically is a key maintenance procedure to improve vacuum performance and minimize the possibilities of pump failure.

Background

The rough pump fluid should be replaced if the pump fluid appears dark or cloudy or after every six months of operation. 

Items Required

• Clean chemical resistant gloves
• Safety glasses
• Funnel
• 10 mm hex key
• Paper towel
• Small plastic tub or other suitable waste container
• AVF 60 Gold synthetic pump fluid (p/n 6040–1444).
  
  

  Caution: Use only the rough pump fluid appropriate for your pump (AVF 60 Gold oil for Agilent MS40+). The use of any other fluids can substantially reduce pump life and will in validate the pump warranty.

Steps to Follow

Warning: Do not touch the fill cap or rough pump until they are cool. The fill cap and pump can be hot. Wear chemical resistant gloves and safety glasses when replacing the pump fluid. Never add or replace the rough pump fluid while the pump is on. Hot oil can splash out and cause injury. Do not touch the fluid. The residue from some samples can be toxic. Properly dispose of the used fluid as per the AVF 60 Gold fluid MSDS shipped with the product.

1. Vent the LC/MS. Turn off the instrument at the front panel power switch and allow the heated zones to cool to below 40 °C. Ensure that the rough pump is cool enough to handle safely. 
   
   

   Tip: Draining the pump fluid while it is still warm, but not hot, will help with removal of the old fluid from the MS40+ pump.

      
2. Unplug all power cords connected to the LC/MS instrument from their power outlets. If your LC/MS instrument includes a pump expander box, make sure you unplug both the main power cord and the pump expander cord from the wall outlet.
3. Remove the drain plug by rotating in a clockwise direction using the 10 mm Allen key. Place a waste container under the drain cap and remove by rotating the drain cap in a counterclockwise direction using the 10 mm hex key (see Figure 1). Allow the used fluid to drain completely into your waste container.
   
   

   Caution: The older petroleum-based pump oils SW60 (supplied in kit p/n 5190–9008) or AVF60M (p/n 6040–1361) should not be mixed with the current synthetic pump AVF 60 Gold fluid. There is no need to rinse out the old oil, but allow sufficient time for the pump to fully drain.

    
   Figure 1. Draining used fluid from the MS40+ pump

4. Reinstall the drain plug and tighten in a clockwise direction using the 10 mm hex key (see Figure 2).

   
   Figure 2. Replacing the drain plug

5. Use a funnel to add new AVF 60 Gold fluid to the pump until the fluid level matches the maximum mark located next to the fluid level window (see Figure 3):
   
   

   
   Figure 3. Refilling pump fluid to the maximum level marked next to the fluid level window

6. Reinstall the fill cap and tighten in a clockwise direction using the 10 mm Allen key (see Figure 4):
   

   
   Figure 4. Reinstall and tightening the pump fill cap

7. Record this procedure in the Maintenance Logbook.
8. Plug all power cords removed in Step 2 back into their power sockets and ensure power supply to the instrument and the rough pump.
9. Turn on the MS front power switch and monitor the pump down process. The MS-40+ is a slow-start pump. There is a loud noise as the pump slowly starts, then the pump noise will reduce as the pump gets to full speed. Listen for the sound of the MS turbo pump spinning up to operating speed as a sign the MP-40+ pump is working normally.

Learn how to effectively operate and maintain your Agilent 6000 Series LC/MS system: LCMS-6400-1201s - Essential Housekeeping Tasks and Best Practices for Agilent 6400 Series LC/TQ e-learning course available from Agilent education