I think I've improved the seals on the main air baffle.
Therefore I cut that section out from the long seal and reinstalled it.
There is clearly a leak on both sides along the cowl doors. I stuck "T" pins in the edge of the felt so I could determine where and how big the gap really is.
The doors were fastened shut to push the pins into the felt.
With the light behind the seal I could see that the pins were not pressed too far down.
This gave me a pretty good idea where and how much the seals needed to be widened to get a good seal like in the center.
I cut new pieces and this time I used some spray adhesive to bond the felt to the aluminum, in addition to the staples. I masked everything to keep the spray only on the baffle.
The new sections are quite bit taller than the old ones so I trimmed them with the scissors to make a smooth blend.
I also used the scissors to put about a 30 degree chamfer on the aft edge to make it more flexible. I left the top edge about 1/8" wide and ran the chamfer down the back about 3/4" - 1". The idea was that this tapered section would tip forward and seal better against the cowl doors.
I made more new staples from 0.041" stainless safety wire, as before, to secure the felt to the baffle.
When I got it all done I found I had a slight gap at the piano hinge for the doors. I split some felt to about 3/16" thick to make patches for each side. I glued these to the main pieces and redid the staples, again.
These patches fold over nicely under the hinges and should seal very well.
I also widened the pieces under the rocker covers, on each side. I had previously moved them outboard, but I don't think they were sealing good enough. Now they really press against the cowl.
I like how these came out, but I need to fly the plane to see if the cooling problem is solved.
We have a week of warm sunny weather coming so hopefully that will happen soon.
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