1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Hood silencer?

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Old Jul 20, 2014 | 12:03 PM
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Hood silencer?

Anybody have any good tricks to make your hood sound a little less ridiculous when you close it? Maybe dynamat if it can handle the temperature? Regular hood insulation?

Sounds like somebody smacking a metal garbage can with a baseball bat. Decidedly the least sexy sound the car makes.
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Old Jul 20, 2014 | 01:50 PM
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When I restored my car i addressed this issue by using several dabs of strategically placed seam sealer between the frame of the hood and the hood skin. This stopped the hood skin from vibrating which caused the sound, part of the reason I did it was because my original hood had a crease from one time when it got slammed too hard. I was hopping to kind of reinforce it so that wouldn't occur again, but it also helped with the sound as well.
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Old Jul 20, 2014 | 01:56 PM
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From: https://www2.mazda.com/en/100th/
Originally Posted by rwatson5651
When I restored my car i addressed this issue by using several dabs of strategically placed seam sealer between the frame of the hood and the hood skin. This stopped the hood skin from vibrating which caused the sound, part of the reason I did it was because my original hood had a crease from one time when it got slammed too hard. I was hopping to kind of reinforce it so that wouldn't occur again, but it also helped with the sound as well.
i've done the same, and it goes from metal garbage can to mercedes.
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Old Jul 20, 2014 | 05:15 PM
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Ah! That makes sense! I didn't realize it was the hood rattling against the frame. So is this something that has to be done with the frame separated from the skin?

I'm going to have the car professionally painted in a month or two, so that sounds like a great time to do it.
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Old Jul 20, 2014 | 08:31 PM
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You just squirt dabs of seam sealer in between the frame and the hood from underneath, no need to take it apart. And the skin doesn't actually rattle against the frame, it just vibrates enough to be noisy.
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Old Jul 21, 2014 | 08:32 AM
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Originally Posted by rwatson5651
You just squirt dabs of seam sealer in between the frame and the hood from underneath, no need to take it apart. And the skin doesn't actually rattle against the frame, it just vibrates enough to be noisy.
Right on time. Name/brand please?
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Old Jul 21, 2014 | 08:51 AM
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I kinda like the tinny rattle of the hood. It's a noise that instantly signifies that someone has been tinkering on a 1st gen.
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Old Jul 21, 2014 | 09:57 AM
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Originally Posted by Siraniko
Right on time. Name/brand please?
Any generic brand will do, any auto body supply will have tons of it. Here is one from Eastwood:
Eastwood Seam Sealer Cartridge

One from Summitt Racing:

http://www.summitracing.com/parts/sm...FQQQ7Aod4FoA0A
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Old Jul 21, 2014 | 10:33 AM
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I've used silicone for the same thing; it works okay, but it tends to pick up dirt over time. Seam sealer sounds like a better solution.
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Old Jul 21, 2014 | 11:37 AM
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Cool thanks. SEM is not hard to get locally.
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Old Jul 21, 2014 | 12:56 PM
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Wind gets under the passenger side of mine while driving and causes it to flutter a bit. Post pictures of your seem sealer.
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Old Jul 21, 2014 | 01:19 PM
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Originally Posted by MosesX605
I kinda like the tinny rattle of the hood. It's a noise that instantly signifies that someone has been tinkering on a 1st gen.
It's the sound of lightness! For real.

...but I would like to see pics of the seam sealer as well.
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Old Jul 21, 2014 | 03:33 PM
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Lol yeah any thing above 65mph and my hood looks like it's going to take flight.
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Old Jul 21, 2014 | 03:53 PM
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Originally Posted by project7s
Lol yeah any thing above 65mph and my hood looks like it's going to take flight.
Annoying as hell right? There is a road that regularly runs 85 mph headed to Duluth and man, does that hood bug me. I've seen a few posts here that deal with it, but none that I like how they looked well enough to go jump on it. If this is just a little bead that puts enough pressure on the hood to keep it from wobbling this could get added to the list.
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Old Jul 21, 2014 | 06:21 PM
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Ground control to major Tom. Mine too flies with the wind. Cept mine is on the drivers side. I get a real good view of this. Thought I was special. Glad I'm not. Lol

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Old Jul 21, 2014 | 07:09 PM
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I'm too lazy to run out to my car and check, but are there adjustment slots on the hood latch that would allow you to "preload" the hood? In other words, to hold it down more tightly?
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Old Jul 21, 2014 | 07:17 PM
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Yes there are slots to align the hood only
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Old Jul 22, 2014 | 07:07 AM
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Any tricks that one should know. Pics maybe. Looks like we could use it

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Old Jul 22, 2014 | 10:45 AM
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If your hood flutters at the corner(s) at speed, you might also check if the rubber stops it rests on have worn down, got lost, or shrunk with age.
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Old Jul 22, 2014 | 11:52 AM
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DD adds a good point. Rubber detoriates over time and re placing or re adjusting the stops can reduce the corner flutter at speeds. The tinny rattle when closing the hood is a seperate issue, but when new they used sealer between the hood pannel and its support which kept the sound to a dull thunk. The first time I heard one reverberate like empty a soup can was very annoying to me. The original sealer must get brittle over time too and loses adhesion. I much prefer the solid thunk. It's one of the little tell tale things you can use to judge a cars true condition and amount of care its recieved.
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Old Jul 22, 2014 | 02:52 PM
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Originally Posted by Banzai
The original sealer must get brittle over time too and loses adhesion.
It does that all right, and eventually pieces of it end up inside the hood between the skin and the inner frame. You can hear them move around in there when the hood is opened/closed. Hell to get out.
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Old Jul 22, 2014 | 06:34 PM
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3M makes a smaller tube of Seam Sealer that doesn't require a Glue Gun.

Amazon.com: 3M 08551 Clear Auto Sealer - 5 fl. oz.: Automotive Amazon.com: 3M 08551 Clear Auto Sealer - 5 fl. oz.: Automotive
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Old Jul 25, 2014 | 09:34 AM
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Here is a pic of the seam sealer I put on my hood:
Name:  7315E931-0240-429D-81F3-7F206819B991_zpsj69kt39a.jpg
Views: 41
Size:  48.6 KB
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Old Jul 25, 2014 | 12:27 PM
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I've got the driver side hood flutter. Tried bowing the hood a bit to fix it and it helped but not
enough. The rubber bumpstops are NLA I think.
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Old Jul 25, 2014 | 12:37 PM
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Well I figured out my problem. I hope its this easy for everyone else. The passenger side flutter was caused by this little guy being backwards. With it backwards it doesnt form fit the edge of the hood properly and the hood basically bounces like a pogo stick on it being that it doesnt close or align right. This picture is the correct way to have the bushing.

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