"Ash Wyllie" wrote in message =
...
Ray Andraka opined
=20
I'm surprised no one has mentioned wet vacuum pumps. I'm considering =
a
wet pump when the current dry pump gives up the ghost, as it sounds =
like
wet pumps are nearly bullet-proof. That said, I have been lucky in =
that I
still have not had a vacuum pump go out on me. I have had several =
gyros
fail though.
=20
At one point I thought about replacing the dry pumps on a Twin =
Comanche with
wet ones. Seems that you need to go through a bunch of STC or 337 =
field
approval paper work to do the swap. So I dropped the idea.
=20
=20
I don't know about Lycoming engines, but Continentals still have the oil =
galleries
under the mounting pads for the vacuum pumps.
I know because I recently had to replace a leaking seal on one of my dry =
pumps.
Probably a simple 337 would suffice for Continentals.
You'd just be changing back to the configuration they were originally =
designed for.
---JRC---