Chris;
Ah, yes.  I was pretty sure you would have it right; but that I didn't
understand.
Of course it wouldn't work on a 20B.

Al

-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On
Behalf Of Ernest Christley
Sent: Monday, February 28, 2011 10:47 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Steve Boese TDC Finder

Al Gietzen wrote:
>>  Al
>
>>
>
>  
>
> Let me offer this idea. If you know where the tip seals are, then you
>
> can derive TDC. Level the base of the engine, and the tip seals should
>
> line up verically. Pull the trailing plug, rotate the shaft until the
>
> tip seal shows up in the first chamber, then make a mark on the starter
>
> ring gear. Rotate the engine until the next seal shows up, and make
>
> another mark. Count teeth to get the center one, or make the two marked
>
> teeth line up vertically. This would eliminate the importance of the
>
> spark plug hole location.
>
>  
>
> I'm not sure I understand this; but it suggests the assumption that the
>
> TDC position is at the trailing plug hole. - which I don't think is
correct.
>
>  
>
> Al
>
>  
>

I'm suggesting that TDC will find the opposing tip seals lined up
vertically.  The first step is to mark the location of
the seals on an externally accessible surface (the starter ring gear being
acceptable), and then use those marks to set
the vertical alignment.

--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:
http://mail.lancaironline.net:81/lists/flyrotary/List.html