Holes in body

[IndyJimW]

My '87 Avanti sat for a while before I purchased it, when I got it chipmunks had left acorns everywhere in the interior. I just removed the gas tank to replace hoses, fuel sender and to install an in-tank fuel pump for my TPI system. While cleaning up more acorns I came upon two large holes in the body in both corners behind the fuel tank. The panel that separates the trunk from the fuel tank compartment and connects to the fuel tank tray is short about 4" wide by 2" deep. You can see the ground behind the rear wheels from inside the car. Is there a reason for these holes or is this just poor workmanship? There is evidence of water getting in from these holes.

[IndyJimW]

Here is a picture of one of the holes behind the fuel tank, are these holes normal or should I cover them?

[Paul K.]

If you can see the ground, then they are not supposed to be there. Water and exhaust fumes will enter from there. If the holes are large, I would patch the holes with some fiberglass, either a carefully cut piece or since this area is hidden, some of that shredded "Kitty Hair", "Tiger Hair" or "Gorilla Hair", all the same stuff. If the holes are an inch or less in diameter you can plug them up with some 3M Strip Caulk, some people call it "Dumb-Dumb". It is automotive sealer for windows, etc. that stays pliable and soft so it seals. The factory used this on Avantis to seal the back seat panel the one with the many screws between the rear seat back and the gas tank. You will need to buy some of this stuff any way to reseal that piece so I would go with that if the holes are small. All these items are available from NAPA.

[IndyJimW]

If you can see the ground, then they are not supposed to be there. Water and exhaust fumes will enter from there. If the holes are large, I would patch the holes with some fiberglass, either a carefully cut piece or since this area is hidden, some of that shredded "Kitty Hair", "Tiger Hair" or "Gorilla Hair", all the same stuff. If the holes are an inch or less in diameter you can plug them up with some 3M Strip Caulk, some people call it "Dumb-Dumb". It is automotive sealer for windows, etc. that stays pliable and soft so it seals. The factory used this on Avantis to seal the back seat panel the one with the many screws between the rear seat back and the gas tank. You will need to buy some of this stuff any way to reseal that piece so I would go with that if the holes are small. All these items are available from NAPA.

Thanks for the info, I wanted to make sure that these holes aren't for ventilation or something. You can't see from the photo but the hole goes to the right another 3", same on the other side of the compartment. I think the easiest way to fill the hole will be with spray insulation foam. The factory filled the area around the fuel tank with pink housing insulation, which held water coming in from these holes and caused alot of surface rust as you can see from the straps. The factory also brought the foam insulation that is under the carpeting up and glued in to the front of the gas tank. If any fuel leaked it would soak int the foam and down into the carpet.

Jim Wood

[Paul K.]

The Studebakers and Avanti IIs did not have any insulation underneath or behind the back seat. This is a place to upgrade and install some modern DynaMat insulation or similar.