>> One more question Joe.
     >> Was the EM2 or the Microtec controlling ignition?
     >>
     >> Paul
     >
     >
     > I have the MicroTech. That's what Atkins sells with his engine
     > package. It seems to be a reasonably complete and robust system.
     >
     > Here's a picture of the broken sparkplug.
     >
     > Joe Hull
     > Redmond/Seattle WA, Cozy-Mark-IV - 71hrs
     >
     > Thanks for the picture Joe.
     >
     > I think a slightly smaller gap might prevent the broken ceramic
     > from dropping below the ground electrodes.
     >
     >
     > Paul Lamar ...No rotor no motor.
     >
     > That is a different spark plug from the standard 2nd gen
     > BUR7EQ-L/BUR9EQ-T? Looks more like the spark plug used on the first
     > gens?
     > Perry Mick

    Thanks Perry.

    Jim Mederer and Dave Lemon, have you seen this failure before.
    The supposition is the ceramic insulator failure took out the
    apex seal. Is this a common problem in racing engines?
    --
    Paul Lamar ...No rotor no motor.

Hi Paul,

    A broken plug insulator usually means the plug was too hot,
detonation - or both.

Jim Mederer

Thanks Jim.

I know it is not a common problem in street engines as there
have been over a million Mazda rotary engines sold and if this
were or is a common problem I am sure Mazda  not have sold a
million engines. This plug was from a normally aspirated engine
with 35 hours of high power running so detonation was unlikely.

So keep checking your plugs guys when the engine is new
to be sure they are not overheating and the plugs are of the right
heat range.

It is the duty of the engine builder to put heat range plugs in
the engine that are consistent with its intended use. If the plugs
prove to be too cold than adjustments can be made later.

Jim, given this scenario what plug numbers would you recommend?

Paul Lamar ...No rotor no motor.

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