Needed a for public facing place to share this photo of my AA5A cowl cooling inlet.
I've been trying to find ways to cool #3 cylinder, looking at the baffle seal (been like this since I bought the plane 18 months ago), I assumed it was right, but think I need to get expert ruling.
This much baffle seal hanging down seems like the airflow will bend the seal downward and cause obstruction. Should it be on the outside of the cowl inlet like this...if so should the seal be trimmed back to prevent it from it dragging into the airflow? My # 3 cylinder routinely stays between 430 and 440F.
It looks like there is a pocket made by the cowl's leading edge (on the other side of the fiberglass) allowing the seal to tuck in the pocket & still laying forward, so it is out of the opening all together & air pressure will still push the seal upward into the roof of the cowl.
Update - 2/6/2015
Overwhelming consensus from the Grumman Gang (thank you)...the baffle belongs in the pocket. I feel a bit silly for not being confident in this presumably self-evident conclusion. I had scoured my pictures from prior to annual and others on the internet, I couldn't find a detailed straight on shot of the cowl inlet...so here's my AFTER pic (#AA5A #Grumman Cheetah Baffle Cowl Nose Bowl inlet):
Last night, I flew from Metro to Centennial to meet some friends and could tell a big difference in the readings off the JPI, most notably cylinder 3 read 40F cooler on climb out. During the short cruise segment, the cylinder and exhaust temps were more consistent between cylinders, allowing for more leaning and power.
Lessons learned:
1. I need better familiarity with the proper configuration of my plane - The baffle seals are now etched into brain, having inspected them at every angle, might try snapping high resolution pics of every inch of the plane...that way I have a baseline. I did this when we built our house, I've successfully used the archive to confirm locations, configuration and routes of services behind the walls.
2. The shop I used seemed to do a great job in 2013 and last year did not. Having the JPI installed during annual seemed too much distraction and there was a new guy who did some of the work...including putting it back together. I need to do an owner assist annual with someone knowledgable and learn it myself.
3. Received feedback from some who observed the JPI reading high by @50F, some going so far as to say I should junk it. I'm not prepared to react without more research. It was the JPI that provided empirical data which forced me to investigate, the issue was my unfamiliarity with the proper config of the baffle. My Operation Science theory suggests keep making consistent measurements and investigate inconsistent readings. Said differently, the JPI may read high or low, it's still useful in reporting deviation from norm. Having the JPI installed, at the exact time the baffle became screwed up, when the pilot was not fully familiar with the baffle config...that chain is broken.
Next fly to KAEG on Sunday if weather is good to attend Hypoxia training and chamber - this will give me 5 hours of cruise with a right seat pilot, we'll have some time to dial in 11U:)
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