Andrew Gideon wrote in message gonline.com...
Bruce Cunningham wrote:

the cure is sometimes that in the rear
inspection covers on the sides of the tail in front of the stabilator,
they have a edge bent outward to scoop air into the tail and keep
exhaust out. These scoops or inspection plates have to be mounted with
the scoop facing forward so that they face the airstream. People have
installed the covers with the scoop facing down or backwards, usually
after an annual etc., and then they start getting CO in the cabin.

Are these the round inspection plates like those one finds all over the
airplane, or something different?

Is the "scoop" really noticable, or a slight bending?

- Andrew

Yes they are. They are a combination scoop/inspection cover. The scoop
is about a 1/4 inch high outward joggle of the inspection plate just
in front of the stabilator. The open part must face the airstream,
that is, forward. There is one on each side. I don't know if 182s have
this. I think maybe some 210s do. If your plane is supposed to have
them and doesn't, in all likelyhood that is the problem. The scoop is
a Cessna part and can be ordered. It was the fix Cessna found when CO
was an issue on the Cardinal RG, maybe other models. My fixed gear
Cardinal does not have them. The exhaust, flow around the fuselage,
and openings are different so it doesn't need them. I sent you an
email with photos of a plane both with and without the scoops. Hope
that's you're problem. It will be easy to fix if it is. Guys have
spent months and thousands of dollars to find a leak when this was the
problem. In some instances, all it took was 5 minutes to turn the
scoops in the right direction, as they don't work if they're not, in
fact they sometimes make it worse.

Regards,
Bruce Cunningham
N30464