Yes, they are in-the-tank pumps. I have both in my sump tank.

On Wed, 17 Mar 2004 09:56:06 -0500, Joseph M Berki wrote
> Perry,
>          Are the Mazda pumps submersible?  Would like to mount them
> in the sump.
>
> Joe Berki
>
> At 06:42 AM 3/17/2004 -0800, you (Perry Mick) wrote:
> >Al Gietzen wrote:
> >>
> >>Perry wrote:
> >>
> >>
> >>
> >>If you are flying and running only one h.p. fuel pump, and that pump
> >>fails, the engine will become silent only milliseconds later!
> >>
> >>
> >>
> >>This is interesting.  As my circuit diagram is currently configured, I
> >>have a pressure switch in the fuel system which automatically turns on
> >>the backup pump if the pressure drops below about 30 psi. (don t
remember
> >>now the exact setting on the pressure switch).  Do you suppose that this
> >>wouldn t react fast enough to keep the engine running?
> >>
> >>
> >>
> >>   There is a manual bypass so I can turn the pump on if I want.  The
> >> idea was to turn on both pumps for takeoff, but at other times the
> >> backup would automatically kick in to keep the engine from stopping if
> >> the primary pump stopped; thereby avoiding rapid heart rates on the
part
> >> of pilot and passengers.
> >>
> >>
> >>
> >>Al
> >That's an excellent idea Al. Probably the best solution. The engine
> >stutters and dies as pressure drops below 20 psi.
> >
> >I just run both pumps all the time. (I get nervous if I turn one off,
even
> >at altitude). I can tell if one has failed because the pressure is
> >slightly lower with only one pump on. Those Mazda pumps are extremely
> >reliable. I use two junkyard pumps that probably had 100k+ miles in cars
> >previously. No failures yet. I've also owned three 2nd gens with probably
> >200kmiles accumulated between them and no failures yet.
> >--
> >Perry Mick
> ><http://www.ductedfan.com>http://www.ductedfan.com