Bill Freeman wrote:

 OK, given that I am an unbeliever, I think there are several
possibilities to help reliability.  Here are some:

  1) Don't fly with a junkyard engine.

Agreed.

  2) Add a static pressurization system like Paul has shown and
      rig up a ground accessible fitting, like in the oil filler door area
      or air outlet area, or somewhere else accessible.  Using a
      REGULATED !!!!!  air supply, bring the system pressure up
      to rated + some safety factor with the engine cold and leave
      while you load fuel, baggage and preflight.  Look for coolant
      leaks with max cowling access for inspection, and loss of
      initial pressure over the preflight period.  Pressure loss or
     coolant leaks are an obvious 'no-go'.

Not a bad idea at all, but you have added another point of failure.  Also, I would be very leery of adding another point of failure on the passenger side of the firewall as someone else said, that leak could obscure your vision horribly and burn you as well.

  3) Consider an emergency cooling system, perhaps drilling the
    water jacket on the hot side for fittings from a pressurized
    tank with an emergency-on valve.   Lose coolant,  punch up
    "nearest airport" on GPS,  change heading, reduce power to
    minimum flyable,  go full rich (perhaps "emergency super rich for
    cooling" setting on Tracy's FI system??) and turn on the "one shot
    emergency cooling system" to dump 2-3 gallons of water into
    the cooling passage at the hottest points thru internal spray nozzles
    to give a slow dump time, perhaps 5 minutes or so.  If you pressurize
    the tank to 75 psi, it will spray the water into the passages and get
   you perhaps 3-5 minutes of extra engine life, maybe more with
   low enough power setting.   Could make the difference between
  landing on a runway or in a field or trees.

I think this is a little extreme for a rotary engine, adding a lot of weight and complexity to an engine that is known for its ability to get you home without coolant.  Perhaps a more limited version with a small amount of water and the aluminium seal stuff.  (I always preferred SilverSeal, but haven't seen it for years.  Emergency full rich stting is a great idea.

  4)  The **best** solution is still to use EXTREMELY high quality
       plumbing on your system.  I do believe that hose clamped
       systems CAN be made reliable (witness all the Hondas and
       Toyotas out there)  IF, IF,  IF they are VERY carefully
       engineered with highest quality hoses replaced regularly and
       *proper* fittings and clamps.   Spring type clamps are the standard
       on Hondas, and I believe are more reliable than screw type, which
       can lose tension  as the rubber crushes beneath them with heat and
       time.   My screw clamps on the air induction tubes (rubber hose
      connectors) of my Lyc are essentially always in need of a bit of
      tightening.

  Feel free to tear this apart and improve it.

No Prob!

Hans Conser

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