Change of Rotary Pump Oil (ULVAC GHD-031)

Required parts

Part name
Required quantity
Tray, NR-374-06
Place the tray underneath the rotary pump to prevent any oil leaks from dirtying the floor, etc. The oil seal of the rotary pump will deteriorate with age. Failure to perform regular maintenance can lead of sudden oil leaks. This tray can prevent the surrounding from being contaminated by oil in such cases. Using this tray is particularly recommended if you are installing the rotary pump on a desk, etc.
Rotary pump oil ULVOIL R-2 (1 L)


The figure below shows the names of the parts of the rotary pump.
★1: Inlet port
★2: Oil supply plug
★3: Oil gauge
★4: Drain plug
★5: Exhaust port
★6: Motor

Step 1

Allow GC/MS to come to an automatic stop. Wait until [Completed] is displayed.

Step 2

Wait for about 10 minutes after the GC/MS has stopped.


Immediately after stopping the instrument, the rotary pump oil will be at a high temperature and could cause burns.

Step 3

Open the drain plug and drain the oil.


Have an appropriate tray or plastic bag ready in preparation of a possible oil splatter.

Step 4

After the oil has been completely drained, close the drain plug.

Step 5

Click the [System Control] icon on the [Main] assistant bar.

Step 6

The [Vacuum Control] window opens.
Click the [Manual Operation >>] button in the [Vacuum Control] window.

Step 7

[Vacuum System] appears in the lower part of the [Vacuum Control] window.
In the [Vacuum System] group, click the [Start] button for [Foreline Pump (FP1)].

When the message "The column may be damaged if you start the vacuum pump while the flow controller is OFF. Do you want to start the pump?" appears, click [Yes].
Wait for about 5 to 10 seconds.


Oil mist may come out of the exhaust port. If that occurs, proceed to step 8 immediately.

Step 8

Click the [Stop] button.

Step 9

Open the drain plug again and drain the remaining oil.

Step 10

If an oil mist filter is attached, remove it so that it does not get in the way of replenishing oil.

Step 11

Close the drain plug and remove the oil supply plug.
Pour in new oil(②) until the oil gauge indicates a reading in the red circle range (approx. 0.37 L).

Step 12

Close the oil supply plug.

Step 13

If you removed the oil mist filter, re-attach the oil mist filter.

Step 14

Launch the [Analysis] program.
Click [Details] on the instrument monitor.

Step 15

Click the [Consumables (MS)] tab in the [Monitor Details] window, and click [Consumables Reset].

Step 16

  1. In the [Consumables Reset] window, enter "0" in the rotary pump oil field and click the [Set] button. After applying the setting, click [OK].

  1. Click [Close] in the [Monitor Details] window to close the window.