Hi Paul...

The Wankel factory in Germany is going thru reconstruction.  I have a contact
here in the US and he is still able to contact the German factory and get
parts.  We have a 75 HP ready for shipment.

When I worked for Libby Welding during the Gulf War...We had John Deere and
Onan diesel engines used for military generators. We did hot room testing for
24 hours and raised the amb temp to 117 deg F. We had thermal couples
installed all over the engine to determine inlet temp, rad outlet temp,
exhaust temp etc. The cooling systems water would boil around the water
jackets because of the 100 % loads placed on the engine at the elevated
temperatures. No Spark Plugs.

I remember the belt tension was critical, amount of coolant was critical, any
kind of internal casting blockage was critical.

Later I worked on a process that was approved by GM to recycle cast iron
cores, exp 4 cylinder engines.  The process to make them cheaper had
eliminated current technology to rebuild them if there were any defects in
the sleeve area.  Boring and pressing a sleeve didn't work that well because
of distortion of the block.  We developed a cold process that allow the
boring and insertion of a sleeve that was secured with a special loctite
formulated for this process.

It worked well on gasoline engines but failed on Diesel applications.  The
temperature transfer during combustion thru the cylinder wall went about 500
deg F and caused the locking agent to fail.

I understand your concern and I will look into that area with additional
testing.  I understand that regular 4 cycle piston engines dump heat thru the
cooling system and exhaust.  The Rotary engine does the same but oil in the
rotor also has a cooling system.

Rick

Juergen Bax is a friend of mine. I was over in Korb Germany last Sept.
It was a real small outfit with only 3 or 4 employees working on the Wankel
company at the time. Most manufacturing was farmed out. They were in a larger 
building with another business making injected molded parts for Mercedes and 
others. Juergen and others bought the business from the former owners
and the engineer there at the time did not design the engine so they had
no experience with plugs up. 

One of the two people that started the
plugs up email list has been working on his Mazda powered  plugs up 
airplane for close to ten years and has less than 34 hours on it. He still
is unable to get it to cool properly at high HP. He started the list
to dispute my contentions and has fostered the bad idea through the mere
name of the list. Yes I know about Andy Venable and his is the exception
to the rule. Most people attempting to fly plugs up engines are having plenty of
trouble with very little actual flying going on. You don't see them at
flyins.

Rotary engines are high HP density engines. Small engine high HP.
Nucleate boiling is what transfers the heat in a rotary engine from the
metal near the combustion chamber to the water. Here is a chart
from Advanced Engine Technology by Heinz Heisler. I also have a large
collection of technical papers on the subject. We discuss these issues on
our free newsletter all the time for the last 2 1/2 years. You are welcome 
to join.

What worries me is the Nickasil wear coating on the Wankel rotor housing has a
tenuous grip on the aluminum. The area around the spark plug can
run to 600 degrees F with a tendency for the coating to flake off.

Paul Lamar

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