covering holes with sound deadening

[dladow]

Greetings, all. My first post since acquiring a 1973 240z two weeks ago. I've been browsing the threads here and have learned alot.

I stripped the interior of the car - no rust, thank goodness. I put down a layer of rust bullet paint on the floor boards and am now laying down Edead sound deadedning material.

Is there any reason why I should not cover the large round holes on the inside door sills with the sound deadening material? Not sure what function these holes serve, but they appear to be covered anyway with vinyl upon completion.

David

[MikeW]

Originally posted by dladow

Is there any reason why I should not cover the large round holes on the inside door sills with the sound deadening material? Not sure what function these holes serve, but they appear to be covered anyway with vinyl upon completion.

I suspect they're there simply to reduce weight. As you said they were covered already so it's not like any air flows through there or anything like that.

[MikeW]

Originally posted by dladow

Is there any reason why I should not cover the large round holes on the inside door sills with the sound deadening material? Not sure what function these holes serve, but they appear to be covered anyway with vinyl upon completion.

I suspect they're there simply to reduce weight. As you said they were covered already so it's not like any air flows through there or anything like that.

[EScanlon]

If you'll note those "holes" actually are pressed into the metal such that they have an indented edge. That indent provides for a lot of structural strength to a piece of metal.

You CAN cover those holes up, just be sure that you've shot some sort of rust protectant into the cavity behind as that is your rocker panel. When I closed mine off, I used pieces of plastic "cardboard" cut into the size of the hole and then siliconed in place before I covered them with Q-Pad sound deadeners.

In my opinion, that makes the car that much LESS noisier.

2¢

Enrique

[TomoHawk]

Whatever material you use, I would suggest something that will let the air pass through, in case there is any moisture accumulation in there. It's so the moisture can evaporate quickly and reduce the possibilityof rust.

[EScanlon]

There is little cross through ventilation going on through those holes. The Z's that I've seen have had the vinyl glued to the inner rocker panel in such a way that those holes were sealed.

Additionally the rocker panel has two drain holes as well as being opened to the reinforcing panel for the door hinges as well as to the rear fender area just behind the locking mechanism.

I used POR as a rust protectant inside the rocker panel, so I wasn't too concerned about leaving it open to ventilation.

I did seal all the holes on the inner rocker panel, the inner rear fender (in front of the rear wheel) and the result is that the car is so much quieter than any other Z I've driven in.

2¢

Enrique

[beandip]

Did you remove all the tar matt that was installed from the factory on the floors. If you havent then you dont know what rust is hiding under the matt. POR is the best rust protection material but it must be applied as the maker says exactly. As was stated before applying POR in the rocker channels is a vary good idea and if shot in with a siphon gun so much the better. These areas "breathe" so if you seal the holes after a rust preventitive it should not be a problem. :classic: