John McLaughlin wrote:

Got the flywheel off today (thanks for the tip, Paul (beat on it with a soft
hammer)) and the engine torn down. It surprised me how fast it goes. I have
two very different questions:

1. I lost 2.5 apex seals on the front rotor. Rotor housing and rotor
definitely show damage, but the front and intermediate housing looks pretty
good (nothing measured yet). I'm assuming these scars (some of the seals are
embedded in the rotor) mean replacement of the housing and rotor. I'm
surprised there wasn't more damage on the side and intermediate housings.
Where did all the metal go? What other parts are susceptible to damage when
the apex seals go?

The metal goes out the exhaust. No valves to get in the way :-)
What you see is what you get in a rotary.

Klause dropped a valve in his O-200 and he at first thought just the 
piston, the head and the valve were damaged. Wrong! The rod was bent too. 
Maybe the crank was cracked. I don't think he magnafluxed it yet. 

Check the rotor bearing surface on the e-shaft to make sure but damage 
there is un-heard of. Also check the e-shaft for run out on the end 
just to make sure.

How did the apex seal break? Was this a turbo engine over boosted or was 
it mis-timed causing detonation?

2. What should I use to clean the housings? The machined surfaces are easy
enough - my carbon build up is all on the rotors, but what about a dumb,
gunky grease on the outside of the housings? How should I protect the
machined surfaces + the bearings?

Thanks for helping a novice.

John McLaughlin

If you don't use carb cleaner nothing to worry about.
Try Coastal Super Power Clean at AutoZone. I also found some stuff in K-Mart
that claims to be ten times more powerful than Simple Green for about
ten dollars a gallon. I put that in an empty 409 spray bottle and then squirted
it on the outside of the engine.  Then I used a garden hose with a small
nozzle to wash it and the grease off. The water pressure does most of the
work. Makes a mess so do it in a field. The spray cans of Gunk don't work 
anymore for EPA reasons I would guess.

Also a suction device nozzle for your air hose will work with water from a 
bucket. It also works great with gasoline but be careful to do it out side with 
plenty of ventilation as that is a real fire hazard.
 
Paul Lamar
 
The Aircraft Rotary Engine Newsletter.              Powered by Linux.

http://home.earthlink.net/~rotaryeng/            http://www.linux.org