Cowl heat barrier material ?

[777drvr]

Hi Guys,

I did a search and didn't come up with anything . I'm refinishing a cowl on my recently purchased 4 and have a little heat damage in two places near the exhausts . There isn't much clearance between the metal and the glass . Only 1/4 to 3/8" . One of the former owners used a thick white ceramic (?)paint as a barrier but it chipped off and didn't work that well .

If I'm going through all this trouble to refinish the cowl , I want to make sure it's protected in the future . What are guys using ? Some suggestions are aluminum tape or a ceramic blanket type material . Any comments are appreciated !

Marc

[Bavafa]

you may want to look into Fiberfrax, spruce carries them. I am using in inside my bottom cowl and seen great result.

Good luck

[noelf]

... I noticed some slight "toasting" of the lower cowling fiberglass. I purchased some Exhst / Cowl Shield from Van's. It is sold in sheet size, is thick Aluminum material with a very sticky adhesive on the back side. I do not have enough time on this material to draw any conclusions...

[Bavafa]

The aluminum sheet VANs sells (at least the one I bought) does not provide much heat protection but it is usually used in the cowl so oil and other things can be cleaned off easily. I used that on top of my Fiberfrax and it is working really great. The Fiberfrax itself does not offer any protection for oil or other contaminate, just heat.

[777drvr]

Thanks Guys ! I'm starting to find a few products that may work well . ACS sells an adhesive backed silica/aluminized reflector material that will probably do the job.


Marc

[Bob Axsom]

When Van changed to the honeycomb core cowl the clearance with the existing Vetterman crossover exhaust was very small and my cowl was almost burned all the way through. After repair I installed this expensive ($78.25) barrier material and had no more problems.

Bob Axsom

[N941WR]

Don't forget to seal the inside of your cowl to keep any wayward oil from working it ways through the pin holes.

My method is to use three coats of epoxy resin mixed 50/50 with Acetone applied with a 3" high nap roller. (Can you tell what I've been doing last night and this morning?)

Once that hardens I cover the inside of the lower cowl with Cowl Heat Protector which is nothing more than aluminum contact paper. That seemed to work wonders with my old engine. I am curious has to how well it will work with this new engine.

[AlexPeterson]

Get some thin (.016) aluminum, and fashion a plate(s) where you need them. Attach them to the cowl in the region of interest with tiny blobs of rtv spaced about on a 1" grid. Do not push the plate tight against the cowl, but allow a small air gap between the cowl and the plate. Anything stuck directly on the cowl will simply transfer the heat right through. Shiny tape might reduce it a bit, but the air gap behind will be 10x better.

[jlk]

http://www.ceramicfiber.net/ceramicfiberblanket.htm

Flexible and weighs almost nothing comes in various thickness. This stuff is similar to space shuttle heat tiles. Just glue a piece on the cowl where the heat is a problem. I think it is also available with a reflective surface bonded to one side which might be better at least keeping oil, etc. out of the blanket.

[777drvr]

Lots of great ideas guys !

Marc