: How often do you change oil? Confirm you have a full flow filter (it
: reads like you do). Does your oil filter have gray (lead) sludge in
: it?
Full flow filter, 50 hours, Aeroshell 80/100 depending on winter/summer. No
lead sludge in the filter, and very tiny (i.e. normal) amount of metal and carbon in
the filter and its element.

: What fraction of the time since you got the engine has been 100LL vs
: autofuel? I assume the autofuel has to be 91 octane autofuel to handle
: your compression?

93 A.K.I autofuel is used for local cruise. Generally at least 25% 100LL on
the takeoff tank. I'd say in the 3-400 hours since we've run it, probably about 60%
on autofuel.

: Have you ever tried to do a mag check at cruise? (i. e. could one mag
: be somehow intermittent at temperature?).

Done in-cruise mag checks. All fine. I generally check it along with my
leaning to verify no rough on just one mag.

: Be sure to check inside the rocker covers to see if the rocker shafts
: are wearing on the cover sides. I found one (but only one) in my 172M
: (1700 TT over 31 years) that was worn substantially. Later shafts have
: a nylon thrust boss.

Will look when I get them off. Probably take a look on Saturday.

: You gotta post what you find. THX

Will do.
-Cory

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************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
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