wrote:
: This may be a shot in the dark, but many years ago we had a similar problem
: (slight sag in power during initial climb) with the O-320 in a Cherokee-140.
: After some troubleshooting we determined that most of the lost power could
: be restored by significantly leaning the mixture. That led us to determine
: that the cause was a partial obstruction of the intake air path between the
: air filter and the carburetor, causing the mixture to be excessively rich.
: I don't recall what the obstruction actually was (or how it got in there)
: but it seems that it would be most pronounced at high power and high nose-up
: attitude.

: If you haven't done this already, next time the "sag" occurs, see if leaning
: helps a bit. Sorry if you have previously reported that you've already
: tried this.

We're going to pull off the induction system and carb to just check for
oddities before putting it back together. We'll take a look.

As far as leaning goes, that's one of the first things I try when it acts up.
Field elevation here is 2100', so (especially in the summertime with DA over 4000')
some leaning is required for best power.

-Cory


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