cowling heat paint

[Flyairth]

The protective heat paint on the inside of my engine cowling is peeling and flaking in places. Suffering a little sticker shock at $3400 for repair, including 16 hours for mostly sanding, I guess, and some painting. Thought I'd share the photo here and ask if anyone had a comparable repair.

Don't know the correct term for the rubber gasket that forms a large rectangle on top of the engine, but is that supposed to prevent this kind of heat/exhaust damage? It got folded back one time the cowling was replaced, and probably didn't "seal". That's my naive guess as to why it got so bad. Other explanations?

[Rich]

This looks like more than just damage to the paint. What does the outside look like? Does the plane have a Powerflow exhaust system?

[Flyairth]

This looks like more than just damage to the paint. What does the outside look like? Does the plane have a Powerflow exhaust system?

No discoloration or bubbling on the outside. Yes, it does have the Powerflow exhaust system.

[astaib]

I sand it myself with first a kasher and then a metallic squeegee.
Then I repaint it and apply antifire patch in aluminum.

Cost me roughly 100€

[Rich]

I don't see the cooling baffles having a part in this. It looks to me like combustion gases ejecting from the exhaust system impinging on this area of the cowling. You really need to closely examine the exhaust system.

[astaib]

I don't see the cooling baffles having a part in this. It looks to me like combustion gases ejecting from the exhaust system impinging on this area of the cowling. You really need to closely examine the exhaust system.

Be careful with CO

[Rich]

You should also look inside the cooling air duct to the oil cooler, as shown by the arrow:

Scorch.jpg (41.05 KiB) Viewed 1734 times

[Rich]

This would seem to be located about where the clamp that attaches the muffler to the hanger strap is located. I'm guessing here, but possibly a crack has developed in the muffler at that point. I could see stress happening at this location if the ball joint somehow became frozen in place, causing engine vibration to be propagating to that intersection of parts.

More pictures would help to confirm or eliminate.

[CFIDave]

Ian:
When you're ready to have your cowling interior surface repainted with special fire retardant paint, let me suggest SouthTec Aviation at KRUQ. Besides specializing in Diamond maintenance, they now have their own paint shop. A year ago I used them to repaint the insides of both of my DA62 cowlings (under warranty, since the paint was flaking off -- Diamond now uses different paint inside cowlings of newer DA62s).

[Charles]

Be careful if you shop around, make sure they quote the proper paint. I am aware of at least one DA40 that had the inside of its cowling painted with regular matte white paint with no fire retardant properties because the paint shop had no clue and thought it was just a cosmetic repair.