Perhaps  its time for a new front cover. The best place for the  water
rad  is
turning out to be on the spark  plug side of the engine.   Unfortunately
that
complicates the pluming somewhat because the water  pump  inlet and
outlet are
on the other side of the   engine.  Perhaps we should take a page out of
the
RX8 design and  make a new front cover incorporating the  water pump
housing
with  the water coming out  and going in on the other side of the  engine.
Another problem  is the pump should be mounted as low as  possible so
any  drop
in water level will not cause the pump to  cavitate.   We built some
remote
pumps a few years ago that  used  the stock Mazda pump cartridge.  One
other
point is the  pump would be more eff.  if the water  came stright into  the
impeller.  Here are some shots of  that remote pump.  I  am looking for
feed
back here.  Does anybody else have an ideas  they would like to  see
incorporated.


Paul   Lamar

Paul,


A new  housing incorporating some of the  accesories would be
welcome.  I
originally wanted to locate my pump  lower  than the engine toward the
plug
side as  the
exhaust  side has the pipes and muffler to the  augmentor.  I was
going  to
use
the Toyota pump.  I also would like to get a later front  housing so  I
can
use a trigger wheel.  This also   permits mounting the alternator on the
plug
side.

Joe  Berki
Limo  EZ


Mazier Enterprize here in Escondido, CA  makes very light  weight remote
electric water pumps in there racing  aps...Mount  anywhere you want,
firewall, inline off rad,  ect.   The  quality is superb and they have
done this along  time.

They have a variety of units with different flow volumes  mounting
arrangements.  they have a web, check it  out.........

Being  electric does this remove it from AC  use??????????


jeff

Excerpt from my book How to Cool Your  Wankel.

"Some have advocated replacing the mechanical pump with an  electric
pump. The Mazda 13B rotary requires about three HP to drive  the
mechanical pump at 6000 RPM and provide the coolant flow  necessary  to
keep the metal temperature near the combustion chamber  within  bounds.
The flow rate required is on the order of 30 to 40  gallons  per minute."

"In the last 100 years there have been  no  breakthroughs in impeller
shapes that would allow a  significant  improvement in water pump
efficiency. On the contrary  impeller  shapes have been simplified to
lower the cost.  Here  are some  photographs of a  second generation
and third  generation Mazda  13B water pump impellers."

"Therefore it would  also require  about three HP from an electric motor
driving a coolant  pump to  provide sufficient water flow. There are 746
watts in one HP  so  three HP is a minimum of 2,238 watts. Since the
electrical  system  voltage is 12 volts and watts is equal to voltage
times  current it  would require about 186 amps out of the alternator
just to  provide  the required coolant flow. None of the after market
car  electric  coolant pumps available claim that magnitude of  current
drain so  obviously they cannot pump enough coolant to keep  the metal
temperature within bounds in a rotary engine generating 150  HP
continuously. This is not just an opinion. It is based on the laws   of
physics. If one wants to reduce the water flow rate in the engine   and
take one's chances one must install thermal couples near   the
combustion chamber to monitor the metal  temperature."

End  quote.

All electric water  pumps,we have tested so far and that  includes
Mezier do not draw  anywhere near enough amps to to pump the  water at
the required  rate.

High water flow velocity in the  block helps transfer heat  from the
metal to the coolant. If this does  not happen hot spots in  the rotor
housings could occur. The heat  going into the metal is  directly
proportional to how much power the  engine is generating on  a
continuous basis. An electric  water  pump that might work in  a car
where anything over 40 HP is a rare and  temporary occurrence  will not
work in an aircraft engine. One could  be fooled by relying  on the
water temperature alone. The water  temperature could be below  200 F
while the metal temperature in the  rotor housing could be over  500 F
in the hot spots.


Paul  Lamar

I told  my wife to order the book for  Xmas..........


jeff

OK Jeff  thanks. Merry  Christmas.

Paul Lamar
-

Paul,
I've heard people discuss  the option of using an electric water pump versus
a mechanical water  pump.  Most of the time, the reason I hear for  using
an electric  water pump is to save HP in situations like drag racing where
even a little  bit of saved power can make a difference.  In those
situations,
the pump doesn't run for very long at one time, and  having  never actually
used one myself, I've always wondered if an  electric water pump  would be
reliable as a stand alone pump under  long continuous high rpm  runs?  I
read
what you wrote about  electric pumps being unable to  provide enough flow
anyway, and  mechanical water pumps seem to have less  risk of failure.
But  for
sometime now, I've been wondering about the  feasibility of  running two
water pumps simultaneously.  If that is  possible,  what would you think
about
having an electric water pump in the   circuit which could be activated
automatically at a given water temp or  rotor  housing temp to act as a
"booster
pump" to increase flow while  the temp remains  elevated?  It would require
a
temperature  activated controller, but I don't  think that would be a big
problem  for the electronics guys on this list.

Don

I don't think it  would be worth the weight an expense since a mechanical
pump
is so simple  and straight forward. Every rotary engine comes with one.
3 HP is a  pittance in the over all scheme of things.

In terms of overall power  conversion efficiency an electric pump  system
goes
like this. The  alternator is 80% efficient and the electric pump motor is
80% efficient  so the overall conversion efficiency of the system is 64%. For
every  mechanical HP the electric pump is putting into pumping the water
the
engine must put in 1.5 HP into the alternator.

Paul Lamar

Thanks Paul,
I totally agree with the need to keep the mechanical water pump, but I was
really trying to stress adding a second ( electric ) pump to help achieve
cooling of the engine during high stress times like taxiing, climbs, and
really  hot days when we struggle to keep our engines from overheating.  The
drag racers want electric pumps to save every horse they  possibly can.  I
don't care about that at all because my 20B P-Port  should have more than
enough power.  But I do worry about keeping this  thing cool, increasing ( or
not decreasing ) the TBO, and avoiding an  in flight failure.  I would be
willing to add a couple of pounds in  order to achieve this goal, and if the
weight concerned me, try to trim off a  few lbs elsewhere to compensate.  Its
something I'm seriously considering,  but I was concerned that the second
pump might induce a reverse flow situation  unless "one way valves" were used,
kinda like when we plumb 2 fuel pumps into  the fuel system like below.  If
this was done, what would be your concerns  (in addition to weight), if any.
Thanks,
Don

---------------------------------------------------------
It has plenty of water flow for idle. Low HP.  What it needs is more air flow.
Large movable cowl flaps are the best way to go.
Electric fans also help but make sure you buy the high flow versions.
Spal fans seem to be the best.
http://www.spalusa.com/store/main.aspx

Paul Lamar