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TR2/3/3A TR-3A Underside of hood

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On the underside of the hood there is a band that goes across the front and this appears welded to the hood itself. There is also a band near the rear of the hood that is welded at the outer edges and at the hood hinge attachments. This band does not touch my hood at any other point. I am thinking it should be tack welded and seam sealed. Is mine correct or has it broken loose at some point in the last 50 years? I can slide a paint stir stick between the band and the hood. This is the last piece I have to paint to complete my paint job. Thanks Tom
 
I don't "know" the answer to this, but I can tell you that my hood looks as you've described yours. I don't think the rear frame work was ever welded to the skin. I've been considering stuffing the gap you described with some felt, in an attempt to further reduce bonnet rattle.
 
Moseso said:
... I've been considering stuffing the gap you described with some felt, in an attempt to further reduce bonnet rattle.
Click to expand...

I believe that originally there was some kind of felt in there. I've pulled something like it out of one of the hoods that I have laying around.

BTW, the rear brace on my hood is also not welded in the center section. There is a slight gap there.
 
Rear hood brace is only welded to outside skin on the sides. Your welds have probably broken loose. You may need o spring the brace to make it pull the hood in enough to fit. Early TR3's did have two brass rivets right behind the vents that helped hold the brace in place.

Marv
 
Both my TR250 and TR3A originally had felt in that gap between the brace and inner bonnet surface. We pulled out the old felt before painting and replaced with new felt after painting. You can forgo the felt but you'll get sideways glances when you pull up to a red light. That drumming can be very annoying because the resonance point is right at the normal tick over speed.
 
Mallard lent me his old louvered hood which had been run over by a car. It needed both front and rear hood braces. We thought that we would cut the braces out to see if maybe the sheet metal could be metal finished, I had several early TR-3 hoods that I could rob the front and rear cross braces from but they had to be removed from the spare to be able to be installed and fitted to his bent up hood. Rear brace, ground off the welds at the edges and it was removed. Front cross brace was more difficult, three spot welds that had to be located and drilled out from the brace side. The front lip needs to be pryed just a little and tapped with a block and a hammer, it gave up and started to move back. I am still not finished but I am now ready for the next step. Good Luck, Bill C. Mesa, Az.
 
Frank, what thickness of felt did you use and where did you get it? I just checked mine and it does indeed have the felt in there. I need to replace it. I suspect that if I don't, I will end up with a fine dusting of 49 year old felt particles all over the under hood of the car.

Thanks, Dick
 
Hi guys - thought I would resurrect this posting - this came up today at my body shop.

They have proposed squirting in a few dabs of expanding urethane foam to eliminate the rattle. Seems like a simple fix.

Comments?
 
A few years ago I saw a friend of mine spray foam in and onto the roof of his prized 1972 Chevy truck to help keep it cool in the summer. 5 years later the foam had held moisture and rusted his beautiful trucks roof where the foam attached to the inside of the roof. He had to replace the roof. Be careful with the foam and after his experience I wonder about the Second Skin and other insullation material Triumph owners are installing in their cars? Good Luck, Bill C., Mesa, Az.
 
I did, finally, stuff some felt into the gap between the bonnet skin and that rear frame member. It further minimized bonnet rattle. It's not eliminated, but it is now down to a dB level that I can live with.

I don't know about foam -- but I can recommend felt as a slightly unsightly (only when the bonnet is up) and effective solution. And, it only took about 15 minutes to do it.
 
luke44 said:
Dumb question - where is the felt store?
Click to expand...

That's not dumb, I was thinking the same thing! Looks like maybe McMaster Carr could be an option:
Felt
 
Often dry goods stores, the ones that sell fabric, carry an assortment of felt. Some hobby shops also have smaller sizes of felt in stock.
 
DO NOT USE EXPANDABLE FOAM when I painted my TR6 last fall, I had the same Idea, after spending about 40 hours on the hood sanding and repairing all the rust, holes and dents it was ready for paint, sprayed that expandable foam on the underside and it warped the Crap out of it, I ended up buying a NOS hood at 1000.00, in the end I am glad I did since the front of the hood was a huge patch . Hondo
 
The problem with felt is that it's flammable. Might be better idea to use material that is not.

Maybe Dynamat or similar material?
 
JP --
Those listings are all for manufacturers in China -- minimum order 100 square meters.
You got anything a little more user-friendly?

By the way, I got my felt at a local industrial surplus place -- The Axeman. 1/8" thick x 48" wide, I think it was $4.00/yard. I bought a yard. There's some under my gas tank -- some stuffed in my bonnet (need thicker? fold into multiple layers) and plenty left over.
Was there today actually. Enough leather scrap to make a couple of nice, new watch fobs: $1.00.
 
vagt6 said:
The problem with felt is that it's flammable. Might be better idea to use material that is not.

Maybe Dynamat or similar material?
Click to expand...

There's so much flammable stuff under the bonnets of these cars, that I don't think a piece of felt will matter much when the gas line ruptures and pours fuel all over that hot manifold and it erupts into flames.
 
What about using faom wheather stripping,available in numerous widths and thicknesses,and adhevise backed on one side?Gotta go look at my hood.
Tom
 
Hi Tom - I'm not sure if its possible. The felt has to be slid in from the side into a cavity. Sticky one side may be hard to get into place.

Sounds like foam is defintely not the way to go. Hondo - thanks for the heads up on this.

I assume the felt has to extend the full width of the brace (to be effective) so does that mean it's visible from the side?
 
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