Changing oil cartridge on HP5970B turbo pump

[Eluter]

I have a HP5970B detector with a rebuilt turbo pump from 1998 that had been running well up until it got very infrequent use in the last couple years. I'm debating whether to change the oil cartridge in the turbo pump before bringing the instrument back up and was wondering if anyone had experience doing this service.

It requires flipping the detector on it's back and removing the bottom plate of the turbo. There's a oil cartridge and wick for the turbo bearings that can be gently pried out and replaced at very modest cost. Refitting the bottom plate on the turbo re-seats the cartridge at its proper position.

My inclination is to not fix it if it isn't broken and there's a risk of introducing debris into the turbo attempting this maintenance. Then again, this seems like a straightforward operation to do.

Any thoughts or tips on this would be greatly appreciated.

[cleh]

I would not touch it. I have worked with these for over 25 years and have found that if the maintenance has not been done for a while, the pump will fail within a few days after doing it. If I take over an instrument (provide contract coverage) and don't know if the oil has been recharged, I just let it be (if the pump fails, I replace it). I have one instrument that has been running fine for over five years under my watch. I took it on with that turbo running for at least 5 years before me. The customer had no idea or record of cartridge replacement so I decided to let it be.

If you have been doing the cartridge changes when the MS was operating, then it would be OK to change the cartridge before you bring it back on line. You may want to order the o-ring for the cover in case that looks bad.