I was at the hanger last night and noticed my 1961 172B C-300 D had an opening in the center of the lower cowl like it had a light or someting there at one time. The landing lights are on the left wing. I presume this is an altered light position. While inspecting this opening I noticed it is completely capped off in the back. It goes no where.Dead air space.
Questions started popping into my head:
1. What is the old purpose of this?
2. Is there any benefit to blocking it off?
3. Can it be blocked off?
4. Can it be used as a source for ducted air to the rear portion of the engine aimed at cooling the F&M oil filter to help keep oil temps in the green in this 100 deg air...??
Cowl air/hot oil
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
- GAHorn
- Posts: 21309
- Joined: Fri Apr 12, 2002 8:45 pm
Re: Cowl air/hot oil
Your landing lights are in the original factory location.
The square opening below your prop hub is to allow
fresh air cooling for your oil sump...
which is what you are witnessing at the aft end
of that opening....(it is NOT blocked off.)
Do NOT close off that opening.
(On early 172s that opening is also providing
inlet air for your carb heat system, seen at the
side/inside that area.)
The square opening below your prop hub is to allow
fresh air cooling for your oil sump...
which is what you are witnessing at the aft end
of that opening....(it is NOT blocked off.)
Do NOT close off that opening.
(On early 172s that opening is also providing
inlet air for your carb heat system, seen at the
side/inside that area.)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.

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