Sunburn on inside of hood.
 

As a followup to the recently closed thread I am posting the following:

Picture is of a hood on a 65 Corvette a friend of mine owned. The line at the upper right is the blistered paint.
It started smoking in about 5 minutes but only blistered the bottom of the hood since I closed it when I smelled the burning paint.
I think the thing that contributes to the burning is the fact that bottom of the hood is semi-flat black. If it was high gloss it would tend to reflect the heat and possibly not blister the paint.
I have told a few "new" owners of Corvettes about this and a few have ignored it and paid the price.

I currently own the car.

http://i1094.photobucket.com/albums/...ovet/003-1.jpg

I'm amazed at the people that scoff at this problem and think it's a myth. They need to go back to 8th grade science class. I've admonished owners at shows about this but have been ignored so I just walked. I use one of the vendor's cloth covers with elastic for this purpose (a little expensive). I used to just use a towel folded up but I would find them blown down in the engine bay on a breezy day and no help.

I leave the hood closed. :cheers:

Frankie,
I agree with your comments, in summary some people are to stupid to take good advice. I to have been ignored a number of times.
Here in So. Ohio, the land of clouds and rain it still happens.

This is a real problem for all years that have a chrome air cleaner. The sun will reflect off them to a concentrated prism point and WILL burn and blister the paint both under the hood and, sometimes, through to the outside of the hood.
No problem in my case since my 65 has an LS3 with the black plastic intake so no reflection.

I NEVER would have thought about this. While I don't show my car I do work on it with the hood open outside sometimes. The things I learn here!!!

I know this has been discussed to death but...
I take my car to local shows and leave the hood open for hours at a time in the hot Miami sun. I’ve heard these stories and wasn’t sure so one time I took my IR thermometer and took some measurements (yes, some people looked at me kind of funny… but I’m use to that LOL). Anyway, I registered about 7* hotter wherever the sun was focused by the chrome. Not hot enough to do anything but made me realize that under the right conditions, the sun could be focused and do some damage. I now use one of the cloth beanie with the elastic trim and cross flags logo. Not a complete solution because the ignition cover also reflects. Cap Looks good … not as good as shinny chrome but gives me piece of mind. Just got to remember to pull the cover before the judges come by…

Its only a problem with chrome air cleaner that have concave tops. The CI flat cover can be a problem when the retainer nut is snugged down tight. A cover with a concave center with the rest convex can be a problem.

Convex covers diffuse the sunlight rather than concentrate it. I think I learned this is 6th grade science class.


I have had people walk by my car at car shows and inform poor ignorant me, with his convex cover, that the hood will burn. It hasn't, won't ever, and I guess they flunked 6th grade science class, because they don't even want to hear why it won't.

Doug

Good one, Brian!:D

Took the words out of my mouth! What's funny is to see some throw the old dish towel on top of the air cleaner on a cloudy, overcast day so they can answer questions.:D

Just another plus for having FI. Nothing there shiny enough to reflect the sun.

I saw it happen on a midyear at a show years ago, but was horrified when it happened to my silver '63 Split Window at a hot show in July. Wasnt worth the $10 trophy... at least the insurance company didnt think so, trying to match Sebring Silver. :willy:

I am now a believer. It happened to me yesterday with my 65.

This has been an issue since the cars were new; folks who scoff at it simply don't understand basic physics. :thumbs:

I wonder if a shower cap would work? They are pretty cheap.

Maybe one for an alien like ET, those air cleaners are 15"+ wide:D

See post #3.

A word to the wise should be sufficient!
:D

A piece of cardboard or plastic with a hole in the center to put under the wing nut would work. You could even use something with a logo.

If I'm understanding this, it's the concave area under the wingnut that's causing the problem. Why not just put a flat washer (chromed or stainless) under the wingnut?

Not entirely the case....its the air cleaner itself that distorts when the nuts are tightened down...not just the dime sized area under the wing nut.:thumbs:

Yes, the 15" diameter c1 air cleaner, when the nut is tightened down, turns into a 15" diameter parabolic mirror with a focal length of about 80" (estimated), what this means is you get a 3"-4" wide focused spot under your hood (hood up, when reflection is at top edge of hood), that focus spot has about 6 times the sunlight/heat concentrated on it as compared to a 15" wide reflection from a flat surface.

Doug

Gee, all this micro managing the problem.:D

I would have thought:

a) the reflection of the sun caused the problem

b) opening the hood with the sun at the wrong (right) angle

c) an overpolished C1 air cleaner

were the primary causes!