Re: vacuum pump repair

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: <tesla@xxxxxxxxxxxxxxxxxxx>

On Tue, 18 Jan 2005, Tesla list wrote:

> Original poster: Ed Phillips <evp@xxxxxxxxxxx>
>
> It's a little late to ask this, but are you sure the pump needs repair
> to do the job you want?  I use an old Welch pump whose last repair date
> is marked 1/24/54 as a forepump and it still works OK, pulling a couple
> of microns or better.  If the shaft seals don't leak (can be replaced
> for a lot less than you quote for an overhaul) odds are that, with clean
> oil, it will work pretty well after a few hours running.

The pump was given to me, already drained of oil, so I didn't bother to
even run it. From what I've seen, unless you get the pump stright out of
service, it's going to be in pretty bad shape. The oil goes bad and turns
corrosive, something is always leaky (shaft seal, seals on the body). It's
best to clean them up, since you never know what they were used for and
what's lingering in the old oil. The strangest thing I saw was mercury
droplets come out of a small plastic hand vacuum pump like use for
automotive repair. It was new, in the box too.

KEN