Today I went to the airport after about a week of inactivity.

I turned the prop by hand and noticed something really odd.

At one spot

it was really hard to move. I continued to rotate it and the after
several revolution the resistance was about the same all

the way around.

Any ideas?

Finn

Stuck apex seal? Foreign object in rotor housing? Metal particle in
gear box? Drain the oil Finn. Cut the filter open.  Check the
compression.

You guys are probably all aware of this, but I would wager its a carbon
deposit that came loose and got stuck in an apex seal.  I have an engine
with a fair amount of carbon buildup which sheds a carbon deposit every once
in a while, displaying those exact symptoms.  Turning it backwards for
several revs will kick the carbon out of the exhaust ports.

This particular Series V 13BT engine has been sitting in my garage of over a
year.  When they sit for a while, they almost always shed their carbon
deposits, and I can tell how long its been since I last turned it over by
how much carbon it kicks out.  I sprayed some WD40 in the combustion chamber
once - the next week I got quite a bit of carbon out of it.  Alternating
between turning one way and the other seems to do the trick.  A number of my
friends have encountered the same phenomenon.

Jim Ratichek

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