Hi there, I once used the same method as Stewart on one of our Pfeiffer pumps. It worked for 3 years like that until the shaft finally broke. Since then i let a Pfeiffer technician overhaul the pumps every 4 years. Regards Jakov ________________________________ From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On Behalf Of Bishop Stewart Eric Sent: Mittwoch, 9. Januar 2013 14:51 To: [log in to unmask] Subject: Re: [ISOGEOCHEM] Duo 2.5 and DUO 5 Replacement Hi, I experienced similar issues with the DUO 5 in our MAT 253 last year. Upon shut down or power failure( yes, it does occur in Switzerland) the motor energizes but the shaft jolts and holds and does not rotate. The solution was to remove the pump, plug it into an external power source, remove the motor fan cover, power on and manually turn the fan with a quick finger action. Run it warm and reinstall. It seems once it's going it keeps going until it has no power again. This has worked successfully a few times now, we know the shaft or bearings are well on its way.........but we managing to get full use of the pump. Regards, Stewart From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On Behalf Of Hill, John Sent: 09 January 2013 11:04 AM To: [log in to unmask] Subject: Re: [ISOGEOCHEM] Duo 2.5 and DUO 5 Replacement Hi David We had this problem with the Duo 2.5 where the drive shaft fails. Pfeiffer wouldn't repair it they just want you to buy another pump. The same with the DUO 5, they will not start so we disconnect the inlet and then run it for a minute or so then connect it back up. We are slowly switching over to using Edwards pumps although they are larger in size and put them outside the cabinet. We replaced the Pfeiffer DUO 5 on the MAT253 and the Edwards pump fits inside with one other inlet pump. Regards John Hill Mass Spectrometry Facility University College London Chemistry Dept. From: Stable Isotope Geochemistry [mailto:[log in to unmask]] On Behalf Of Denhaan, David Sent: 08 January 2013 17:50 To: [log in to unmask]<mailto:[log in to unmask]> Subject: [ISOGEOCHEM] Duo 2.5 replacement on the Delta V Dear List, The Duo 2.5 roughing pump on my Delta V failed and I need a replacement. Pfeiffer no longer sells that model. Can I use their Duo 3? Peiffer wasn't sure if there were any modifications needed for use on the Delta V. Thanks, David Denhaan NLAE-ARS-USDA Ames, IA This electronic message contains information generated by the USDA solely for the intended recipients. Any unauthorized interception of this message or the use or disclosure of the information it contains may violate the law and subject the violator to civil or criminal penalties. If you believe you have received this message in error, please notify the sender and delete the email immediately.