Factory Floorboard holes?

[56sedandelivery]

So there are some small holes in the floorboard that look like been there from the factory.What were these for and do I need them or can I just weld them up There are 6 of these in the front and do not know if more in the back. Thanks

[scicala]

Those holes were not there originally. All I can think of is someone drilled them to drain water if there was a leak somewhere.

Sal

[56sedandelivery]

Not drilled. Looks like they were punched. Anyway if they were not factory I will just weld them up and be done with it.

[paul2748]

Speculation - my 64 Fairlane rear rug was held in place by some kind of push in things (don't exactly remember what they looked like). I wonder if the same things were used in the earlier cars.

[mercman from oz]

Mystery holes in Floorboard. Question - are they original?

[miker98038]

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I’ve had a number of older cars that had holes of one sort of another, punched most likely. They had plugs with old putty around them. I just thought they were an assembly line deal. Some kind of jig for alignment, welding etc.

I put new plastic plugs in with sealer and went on with the interior work.

[Dobie Gillis]

Often the larger ones are access holes for various things such as transmission fill plugs, etc., or drain holes in case of a lot water entering the interior.

[dmsfrr]

IF a vehicle originally had carpet some of the edges could have been held down with little 'drive nails' thru the carpet into the sheet metal.
Not too likely in this case since the holes aren't around the edges and a Sedan Delivery probably didn't have carpet. Maybe for a rubber floor mat of some sort?

https://www.classictbird.com/Drive-N...tinfo/352802S/
.

[56sedandelivery]

Have no idea if original or not but have been there since I have owned it mid 80s sometime. Car had been somewhat modded when I got it. Bucket seats, but do not remember if there was carpet in there or not.

Originally Posted by mercman from oz

Mystery holes in Floorboard. Question - are they original?

[Daves55Sedan]

On the '55 and '56 full size cars, there were roughly 3/16" diameter factory punched holes for the rear wiring harness clips along transmission hump and rear floor panel. Aside from the larger body-to-frame mounting holes, those are the only factory punched holes in the floor panels.
The factory (depending upon which body plant it came from) usually poured a molten bituminous/tar sealant all along the stiffener tunnels in the floor panels and seams after all the resistance welding is done. And they weren't necessarily neat about it. The purpose of the sealant in the stifferners was to prevent floor covering materials (carpet or mat, whichever was used) from sagging down into these tunnels and ruining the appearance of the floor covering.
Auto restoration people can simulate this by purchasing a bucket of roofing cement and trowelling the goop into the stiffener tunnels and seams.
Years ago, when I redid my floors, I used a caulking gun and tubes of "Grundy" plastic cement on the seams. I think they went out of business, but nowadays, you can pick up a product called "Black-Jack" at the hardware store in both buckets and caulk tubes. Its the equivalent of "Grundy's". Both are asphalt-based roof patch material.

[56sedandelivery]

Hmm These do not appear to be that large. More like a small punch was used. There are three on both driver and pass sides. Never thought of filling the channels to smooth it out. Thanks for that.

[Daves55Sedan]

There is one hole I forgot in the front driver side floorpan. It is a 1/4" square hole for the flat-headed carriage bolt that goes through the floor so you can attach the one-hole strap to the speedo cable under the floor.
In many cases (where floors are rotted out badly), some owners never knew this ever existed and just left the speedo cable dangling on top of frame rail under the floor there.
We are assuming all floor panels were treated with same punching operations and I think that is true. But some of the body plants may have issued a directive to manually punch small "weep" holes in the tunnel sections of the floorpans while other plants did not. If so, they couldn't have been too effective after the goop was poured into the tunnel areas of the floorpans.

[Jwawhite]

What I found in the floor may be described as dmsfrr described. I think they may have been used for the pad under the carpet. I do have various body rubber plugs in my car, inner quarters behind Rr wheel, behind front wheel at the face- to-the-rocker, floor pan and one in the spare tire hole. AND?

[Daves55Sedan]

I didn't mention the large 1-1/4" holes for the rubber plugs, because he is talking about some very small holes. Also didn't mention the holes for mounting the gas pedal because the holes he is talking about are in the middle of those stiffener tunnels.
BTW, ever heard of anybody undoing all the screws from their door threshhold aluminum scuff pads to gain access to those big rubber plugs?
The floor panels on both my '55's were either gone enough or weak as paper, I cut them out and replaced the floors with new panels. The new replacement panels don't come with any holes prepunched, so I didn't cut out those large holes for the plugs, knowing that I would never pull up my rubber mat. Instead, I sprayed a good coat of quality marine primer on the interior floors and then a good enamel overcoat. The rubber mat in my car is over 30 years old and when they get old they become brittle. It is already cracking in spots without ever having disturbed it.

[Daves55Sedan]

I didn't mention the large 1-1/4" holes for the rubber plugs, because he is talking about some very small holes. Also didn't mention the holes for mounting the gas pedal because the holes he is talking about are in the middle of those stiffener tunnels.
BTW, ever heard of anybody undoing all the screws from their door threshhold aluminum scuff pads to gain access to those big rubber plugs?
The floor panels on both my '55's were either gone enough or weak as paper, I cut them out and replaced the floors with new panels. The new replacement panels don't come with any holes prepunched, so I didn't cut out those large holes for the plugs, knowing that I would never pull up my rubber mat. Instead, I sprayed a good coat of quality marine primer on the interior floors and then a good enamel overcoat. The rubber mat in my car is over 30 years old and when they get old they become brittle. It is already cracking in spots without ever having disturbed it.

[Jwawhite]

Also the grooves pressed into the floorboards were partially filled with some sort of deadener? I guess for sound and strength. Under my sill plates is just the metal on my Wagon. And there are the bendable clips to route the rear wiring up to the center floor bottom of the dash. Painted floor with that two coat sealant. POR 15?