Bouncing Hood
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Pro
Joined: Jan 2001
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From: Mt. Laurel NJ
Bouncing Hood
Here is an interesting little problem. On the way to a show this morning I noticed my hood was vibrating. Kind of bouncing. It looks like the bond to the supports underneath have broken loose. I assume that the skin of the hood should be "glued" to the cross supports underneath. Question is, how do I reattach it without distorting the hood.
Always something
TNX Jim
Always something
TNX Jim
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Re: Bouncing Hood (Jim_C)
Jim
My understanding is that the condition of your hood is fairly common -- hoods need rebonding of the skin to the supports as the original bonds break down over time from extreme heat, vibration and constant underhood air pressure from high pressure ram iir effect at speed. If you look at the undeside of the hood you will find original bonding at specific points that is indeed separated of cracked.
I have a 66 Big Block hood which exibited the same condition. The original resin material (not putty) can be carefully reapplied and the hood will once again be tight. I had this completed by a professional corvette restorer with excellent results. The bonds look as original from the factory.
My understanding is that the condition of your hood is fairly common -- hoods need rebonding of the skin to the supports as the original bonds break down over time from extreme heat, vibration and constant underhood air pressure from high pressure ram iir effect at speed. If you look at the undeside of the hood you will find original bonding at specific points that is indeed separated of cracked.
I have a 66 Big Block hood which exibited the same condition. The original resin material (not putty) can be carefully reapplied and the hood will once again be tight. I had this completed by a professional corvette restorer with excellent results. The bonds look as original from the factory.
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Pro
Joined: Jan 2001
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From: Mt. Laurel NJ
Re: Bouncing Hood (66BBCoupe)
Thanks for the replies. There are several gobs of what may have been non hardning putty at locations around the cross braces. After all the years it is quite hard, which is probably why it seperated from the hood skin.
CUL Jim
CUL Jim
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From: Austin TX
Re: Bouncing Hood (Jim_C)
Only the outer perimeter of the hood is bonded with panel adhesive to the hood support. The center is “glued” with some type of mastic or non-hardening adhesive. You can use a paintable caulking of construction adhesive to repair. Don’t use panel adhesive – you need the flexibility to prevent any distortion of the hood skin.
Rob
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Rob
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From: Washington Michigan
Re: Bouncing Hood (l78vetteman)
The original material between the cross-braces and the hood wasn't resin - it was a vinyl plastisol-based non-hardening adhesive, called "gumdrops" or "mastic" in the plants, which hardened somewhat in the paint ovens; it was there to stiffen the hood and to prevent rattles between the inner and outer panels. Your local automotive paint supply house should have a similar material if you ask them for "gumdrops" or "hood mastic".
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Pro
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From: Mt. Laurel NJ
Re: Bouncing Hood (JohnZ)
JohnZ
I'll give those two names a try at the parts stores.
I wonder if a short bead of black RTV placed in between the hood skin and cross brace would work? I could leave the existing "gumdrops" in place so as to hide the RTV. It would look original and have a flexible cushion to prevent the bouncing. What do you think???
CUL Jim
I'll give those two names a try at the parts stores.
I wonder if a short bead of black RTV placed in between the hood skin and cross brace would work? I could leave the existing "gumdrops" in place so as to hide the RTV. It would look original and have a flexible cushion to prevent the bouncing. What do you think???
CUL Jim
