Body / Glass: Need advice on Under Hood Insulator

[wdills]

I have a new under hood insulator blanket from SI. It has some type of backing material and the rest appears to just be a thin sheet of a loose fiberglass type material. I assume the backing material gets glued to the bottom of the hood and the fiberglass like stuff is what you see when the hood is up.

How durable is this fiberglass type material? I don't want this stuff shedding fibers every time I go down the road.

Would I be better off with undercoating or maybe bedliner material on the bottom side of the hood?

Thanks
Wayne

[57pack]

On our 1963 Wagonaire the hood insulation was mounted reverse of what you describe.
The fiberglass matting was glued to the underside of the hood with the black matting material facing down toward engine compartment.
Bought a replacement from Newman & Altman and reinstalled it the same way without issue.

[StudeRich]

The harder surface protects the soft fiberglass from the fan blowing it away.

[wdills]

Ok, that makes sense. So my next question is what type glue should I use to attach it to the bottom of the hood?

I am assuming the underside of a 61 Hawk hood is supposed to be body color. Can someone confirm or set me straight if I am wrong about that too.

[57pack]

We used 3M Trim Adhesive in a spray can. Don't have part number right now as I am away from my garage.
Available in other brands as well and from your local FLAPS, don't use the chain stores so don't know if they have it.
As for underhood color, should be body color if memory serves me well.

[fpstude]

Here is a photo of the underside of our '63 Hawk hood. I assume it is original. Note that is is not centered, but away from the battery side. The underside is body color.

[Skip Lackie]

3M Super Trim Adhesive, product #8090. They make several lighter duty adhesives, but this is the one that is designed to fight gravity, like on headliners and underhood mats. Use it exactly as the instructions direct.

[wdills]

The new mat I got from SI is a lot bigger than the one in the photo posted by fpstude. Thanks for the photo by the way. The new mat is big enough to cover most of the bottom of the hood. Is there any reason why I should not let it go full width? What was the reason for off setting the original away from the battery? Clearance?

I was hoping the 3M spray adhesive was the right stuff. I always have that stuff sitting around.

Thanks
Wayne

[Corvanti]

another "vote" for 3M Super.

if you don't have a clearance issue with the hood, the material and the battery (or other parts) - i'd do the whole underhood!

take some pics and share if you can.

[WCP]

I agree with the photo in post #6. On Hawks, 63 & 64 for sure, have the fibreglass side toward the engine. My '63 Canadian built GT was that way from the factory. I also have a NOS hood liner for a GT hawk with A/C. The cutout for the compressor pulley dictates that the fibreglass side goes toward the engine. The Larks appear to be opposite to that in liner placement.

[Radsman]

As can be seen on post #6 photo, the original hood insulators were yellow colored fiberglass, not grey as the SI ones are.

[sailingadventure]

I didn`t like the insulator I bought for the Avanti so I made one myself.

[wdills]

Here is a more basic question; what was the purpose of the insulator? Was it for noise or was it trying to keep engine heat from damaging hood paint?

[TWChamp]

Here is a more basic question; what was the purpose of the insulator? Was it for noise or was it trying to keep engine heat from damaging hood paint?

I would say for both reasons.

Be sure to keep mice and chipmunks away, as they love to chew on the fiberglass.

[studeclunker]

Generally speaking, the engine doesn't generate sufficient heat to damage the paint. Also, notice the location of your original insulator. If the purpose was heat insulation, then the entire interior surface would have been covered. They do make a difference in the noise transferred to the interior of the car. However, it still sounds like a sewing-machine to me.