Exchanging the Needle Assembly on Agilent G1367A-D Autosamplers

Answer

This Information Applies To: Agilent Autosampler modules G1367A, G1367B, G1367C, and G1367D.

Issue:

The removal and installation of the needle assembly in these older autosampler modules can be tricky and may require patience and the correct technique outlined in the procedure below.

Steps to follow:

Warning: Especially when toxic or hazardous solvents are used, be aware that fluid may leak out during the procedure. Wear PPE as described on the safety data sheet supplied by the solvent vendor.

Warning: When operating with HPLC needles, it is recommended to use the silicon safety tube shipped with your needle assembly to cover the needle tip to avoid puncture wounds.

1. To change the needle, go to your Lab Advisor Software or Instant Pilot Module and, under Service & Diagnostics. Select the corresponding Maintenance position (Figure 1, depending on your Lab Advisor Version, this may look different).

   
   Figure 1. Set the Change Needle Position of G1367A-D
   
   

2. Remove the doors and sample tray of your Autosampler (Figure 2).

   
   Figure 2. Removal of the doors of the Autosampler

3. Cover the needle with a clean silicon safety tube.
4. Unlock the needle lock system and loosen the loop capillary fitting on the analytical head (metering device) side, then pull away the capillary fitting (Figure 3).

   
   Figure 3. Unlocking the needle lock system and loosening the loop capillary fitting on the analytical head

   
   You can draw out the solvent from the loop capillary protection tube with a syringe or leak kit.
5. Remove the loop capillary corrugated waste tube.
6. Pinch the holder clamp, pull back, and remove the needle assembly with the loop capillary from the needle carrier (Figure 4).

   
   Figure 4. Removal of the needle assembly
   
   

7. Pull out the loop capillary (still mounted to the needle assembly) from its protection tube (Figure 5).
   

   
   
   Figure 5. Pulling out the loop capillary

8. Attach the 5/16"-wrench to hold the assembly in place and use the 4 mm wrench to loosen the fitting of the loop capillary. Pull the capillary out from the needle assembly (Figure 6).
   
   

   Caution: Be careful not to bend the sheet metal of the needle.

   
   
   Figure 6. Pulling out the loop capillary from the needle assembly

9. Take the new sample loop capillary and/or needle assembly and reverse the process shown in steps 2 to 8 to reinstall the loop capillary and new needle assembly into the autosampler.
   When inserting the loop capillary into its guiding tube, it might help to wet the capillary with isopropanol before insertion and twist the capillary while pushing it into the protection tube. The rotation will help in getting the loop capillary through the 90° angles in the guiding tube at the back of the module (Figure 7). When it comes out of the tube above the metering head, proceed with the next step.

   
   Figure 7. Inserting the new loop capillary

10. Make sure to push the end of the black chain into the back of the new needle assembly until you feel the stop. Also check the black chain for any broken links or if the chain has come loose from the back of the autosampler. The black chain must be correctly inserted at the back of the needle assembly and firmly attached to the back wall of the autosampler, otherwise alignment problems may occur. See step 11.
    
    
11. Check the alignment of the needle in the needle pusher of the needle carrier: To confirm that the needle is aligned with the center of the needle pusher, view from several directions. If a small adjustment is required, make sure that the silicon safety tube is still on the needle and covering the sharp point of the needle. Then apply gentle pressure to the middle of the needle to center it in the needle pusher.
    
    
12. Carefully remove the Silicon safety tube making sure to avoid touching the sharp point of the needle.
    
    
13. In Lab Advisor, click Next and end the maintenance position. While the needle is going into the needle seat, confirm alignment of the needle with the needle seat to make sure it is all centered correctly.
    
    
14. Run a normal pump flow through the autosampler in main pass mode and check for normal pressure and any leaks. Often leaks can occur at the fitting on the back of the needle assembly, but the leak can travel through the protection tube to appear above the metering head. Pay careful attention to the source of any leaks and call your local Agilent service representative if you have any issues after completing this maintenance.

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