TRUNK LEAK


Q:

I am frustrated with my 1961 Corvette. I cannot seem to find a way to keep water from leaking into my trunk. I have replaced the trunk weather strip twice now, and it still leaks. I am sure it is glued on properly this time. If I dare to wash the car, the trunk will fill up with water. I don’t mean a little water, I mean a lot. I took my wife on a weekend trip with a Corvette club, and it rained during the night while the Corvette was parked out in the parking lot. We couldn’t put our suitcases back in the trunk for the next days travel because the trunk was so wet. Can you give me any ideas about how to keep the trunk dry?


A:

Thank you for taking the time to write about your problem. I have a few ideas for you:


Firstly, I trust that the fiberglass body is not cracked or damaged in such a way as to let water flow through into the trunk. Only you will know that after a good visual inspection of the body. We all know that the first barrier to water leaking inside is the integrity of the body panels themselves.


If that all checks out OK, let me say that the trunk weather strip isn’t designed to keep water out of your trunk; not directly that is. The trunk weather strip is mostly designed to keep out dust, and water splash. It was never designed to be fully watertight.


The shape of the body around the trunk area is designed to channel water away from the trunk opening so it will flow out and away. When everything is working as it was intended, rainwater will drop into the gap that exists around the trunk lid. It will drop into a trough, and it will flow across the top edge and down the sides to the lower corners. There, in the bottom of the drain troughs, you will notice, are two drain holes; one on the lower right corner and one on the lower left. These small drain openings allow for the water to run out through hoses and drop to the ground under the car. These openings are small, and they get clogged up. The good news is that it is very easy to open them. Use a straight piece of wire, similar to a coat hanger wire. Poke it straight down through the center of the hole. The drain hose goes straight down, so you don’t have to worry about damaging anything. Just below the opening, a hose should be installed which exits through the trunk floor to an area under the car near the bumper brackets. You can see these two hoses if you open the trunk. There are no hose clamps to hold them onto the little fiberglass nipples. They should stay put by themselves. If these hoses are missing, or if they are plugged up, the water will spill up over the lip of the trough and drop into the trunk. The weather strip cannot seal it out.


Incidentally, the same method of sealing was used around the convertible top cover. You will see small drain holes there, and they do the same thing. If they get plugged up, the folding top compartment will suffer the same fate. Trapping water in this area will cause the folding top, if it is down, to get damaged by mildew. It can also cause the folding top hinge pivots to seize due to rust and corrosion.


While we are talking about water drains, have a look at your door weather strips. Notice that, on each door, there is a small weather strip called the “Door auxiliary weather strip”. Open one of your doors and look at it. It is located on the door, just below the upper hinge. This small weather strip is designed to do a similar thing that the trunk weather strip does. It traps the water that drains down through it, and directs the water through a small hole to the space inside the door. The door auxiliary weather strip must be glued tightly to the door so that water cannot leak past it, or it won’t channel the water through the hole and into the inner door area. Once the water enters the cavity inside of the door, it runs down and finds its way out of one of the drain holes in the bottom of the door. There, safely outboard of the weather strip, it simply runs down, over the door sill and away. Those drain holes in the bottom of the doors must be kept open as well. I have seen cars with plugged drain holes that had several gallons of water trapped inside the door. You could hear it splashing around whenever you opened or closed the door. I use compressed air to blow out the clogging from these drains. Often, when I blow them out, water will run out of the door. This is not good for the window regulators and door latches. It subjects them to excess humidity and may cause rusting and corrosion that will lead to early failure of the components.


I hope some of these ideas will help.