647jc

647jc

Well Known Member
I bought some of Vans heat shielding (looks like heavy aluminum foil with an adhesive backing) and plan to use it inside the lower cowl in the area of the exhaust headers. I have also coated the inside of my cowl with thinned epoxy and a very small amount of micro balloons. Was wondering if I should use some of the heat shielding immediately above the engine on the top cowl to prevent over heating of the fiberglass after engine shutdown? I?m not even sure it would help, any other thoughts on this, anyone else use this heat shielding, does it stay stuck to epoxy well?
 
Joe,

I too used that heat shielding on the lower cowl. In my installation I ran it almost to the front of the lower cowling. The reason being is that is where the exhaust manifold is closest to the cowl. In other words, most of my bottom cowl is covered with that stuff.

I did nothing with the top only because I have never heard of it being a problem.
 
A lot of shielding in the bottom cowl is good

I have almost burned up the lower cowl before getting the problem under control. It is now covered with the very expensive aluminum faced thermal barrier sold by Aircraft Spruce. Those pipes put out a lot of heat. The upper cowl is not a thermal problem.

Bob Axsom
 
A/S Part Number??

Bob Axsom said:
I have almost burned up the lower cowl before getting the problem under control. It is now covered with the very expensive aluminum faced thermal barrier sold by Aircraft Spruce. Those pipes put out a lot of heat. The upper cowl is not a thermal problem.

Bob Axsom
Click to expand...

Bob,

Do you have a part number for the stuff from A/S?
 
Heat Shield

I also used shield Bob used after having to do lower cowl repair from exhaust heat. p/n 05/00948 (firewall ceramic blanket). Cowl stays very cool now. Expensive but worth it.
 
I used 1/8" Fiberfrax (from ACS) glued on the lower cowl with spray adhesive adjacent to the exhaust pipes and then covered the Fiberfrax with Van's heat shield extending 2 to 3 inches beyond the Fiberfrax on to the cowl surface. Eighty five hours later; no heat damage to the cowl and the Fiberfrax/heat shield shows no signs of coming unstuck.:)
http://www.aircraftspruce.com/catalog/appages/fiberfrax.php

Fin
9A Flying
 
Van's Heat Shield

On my -8, I originally did not use any heat shield inside the cowl. At about the 40 hour mark, I developed two large blisters near the exhaust pipe that I was fortunate enough to catch before it destroyed the exterior layer. After some epoxy repair, I covered the entire inside of the cowl (top and bottom) with Van's foil type heat shield (probably overkill) and no more problems after 300 hrs. The foil type heat shield seems to do the job.

R. E. "Ernie" Butcher
 
I just received some heat shield material that I ordered from Spruce (pn 05-00948) http://www.aircraftspruce.com/catalog/appages/firewall2000.php and was very surprised by how heavy and thick it is.

Is this the right stuff to use and if it is, what's the best way to attach it to the cowling. It seems glue alone may not be enough to keep it in place.

I'm thinking about returning this and using either p/n 08-06735 that Bob referred to above or Fiberfrax + Van's heavy duty foil.

Any thoughts?
 
We too had small blisters form during phase 1 testing ... We just used aluminum foil tape, the type used by HVAC guys. 500 hours working great.
 
Heat Shield

Joe,
I went to my local hot rod shop and bought header wrap for my KR-2. The wrap is heavy fiberglass weave and looks much like a military style web belt. I wrapped my entire 4 into 1 exhaust sytem and this stuff works. You can put you hand on the exhaust pipes immediately after a flight. Don't get me wrong, it's hot but not scourching hot. I've got 250 hours on mine and it's holding up great with now heat damage to my cowling which is also close to the exhaust sytem. I used stainless steel hose clamps to attach. I'm planning on doing the same to my RV-7, TMX 360. I'm hoping to be flying by late summer. I'm working on paint prep right now.
Charlie Reeves, Tucson AZ
 
How much room do the pipes therefore need?

I have the VANS adhesive foil right to the back edge of the cowl. How much room do the pipes therefore need?

Thanks.

PS I havnt flown yet so dont know if I have a problem.
 
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