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