She's sinking! (Help with leaks)

[nullset]

I'm sure many here are familiar with 'Lake Delorean'. I'm on a quest to fix mine.

Currently, I have the interior mostly gutted. I have replaced the rear outer door seals. The inner door seals are not installed yet because I want to make sure it isn't leaking before reinstalling the carpet, and the inner door seals go over the carpet.

After a recent rain, I opened up the car to see where the water was coming in. There were three main spots:

- Driver side, there was a drip coming down inside the storage cubby, behind the lambda computer.
- Driver side, there was a small drip towards the front of the door jam

- Passenger side, there was a clear stream coming down the fiberglass body, in front of the door jam, along the right wall. I'm not sure where this one is coming from.

Where could the water coming in to the storage cubby be coming from? For the others, I am pretty confident that I'll be able to seal them, but that one is vexing me.

[Patrick C]

For the storage cubby leak, remove the speaker panels and I bet you have these holes like I did. I had a storage cubby leak as well. I put a thin layer of fiberglass over these holes and the problem was solved.

[nullset]

For the storage cubby leak, remove the speaker panels and I bet you have these holes like I did. I had a storage cubby leak as well. I put a thin layer of fiberglass over these holes and the problem was solved.

Is that the easiest way? I've never patched fiberglass.....yikes.

I did locate the body drain under the fuel pump, and it was definitely clogged with debris. I'll seal up the hole in the front on the passenger side with RTV. It looks like there was a leak from the windshield drain, which probalby wouldn't be an issue if the body drain hadn't been clogged.

I definitely have a leak under the battery and in the storage compartment, which likely points to those two holes.

[Nicholas R]

You could use just about anything to cover them. If you have a thin sheet of plastic, you could cut a piece to cover it and RTV it into place. Anything as long as you seal it.

Patrick, do you know if there is a VIN cutoff on these holes? I seem to remember originally they were there to relieve pressure when closing the doors, but eventually considered unnecessary. Just don't know when that change happened.

[MrChocky]

Is that the easiest way? I've never patched fiberglass.....yikes.

I did locate the body drain under the fuel pump, and it was definitely clogged with debris. I'll seal up the hole in the front on the passenger side with RTV. It looks like there was a leak from the windshield drain, which probalby wouldn't be an issue if the body drain hadn't been clogged.

I definitely have a leak under the battery and in the storage compartment, which likely points to those two holes.

Patching fibreglass is super easy. If you have friends that surf or windsurf, they can show you how. Pretty much it's mixing epoxy, layering fibreglass material, and then waiting for it to dry then sanding. And if you make a mistake, it's really easy to redo.

[Patrick C]

Patrick, do you know if there is a VIN cutoff on these holes? I seem to remember originally they were there to relieve pressure when closing the doors, but eventually considered unnecessary. Just don't know when that change happened.

I’m not sure if there is a documented VIN cutoff. It may relate more to how long an underbody sat around before being used, as I’m sure these vent holes were just made with hole saws before someone said “stop doing that”.

The funny thing is back in 2003 when I was trying to hunt down water leaks, no one on the DML, forums, etc knew anything about those holes even existing and never suggested looking there. I happened to see the photo on the tri-fold brochure and noticed the holes and said “ah ha!”

[David T]

There is an extensive service bulletin on body leaks. If you don't have outer door seals you get to much water inside the channel and it will overflow into the cabin.

[FABombjoy]

I'd love to see a modern fix that allows for cabin air extraction.

My doors definitely close with less effort if the opposite window is rolled down.

[SS Spoiler]

how about a lightly spring loaded flap that
releases air into the drivers side pontoon? A nice
perforated grill on the vertical carpeted back panel,
would br discrete....jus a thot...

[nullset]

Well, I definitely had those holes. They are now sealed. I also sealed up the leak I found on the passenger side footwell, and cleaned out the body drain.

Hopefully we'll have a good rain before I put everything back together!

[JBaker4981]

I've got to patch the same holes in my car. You can get to it from the inside of the car.

Here are all of the helpful threads that I found in my searches when I was researching this for myself. I plan to fill the holes with caulking, smooth them down, and cover them with Dynamat type of Insulation.

http://dmctalk.org/showthread.php?16120-Water-in-cubby-behind-driver-no-where-else&highlight=cubby

http://dmctalk.org/showthread.php?3078-Hole-in-fiberglass-body

http://dmctalk.org/showthread.php?11768-Holes-behind-rear-quarter-panels

[81dmc]

I just stuck angle drive caps in the holes with RTV to seal.

[DMC-81]

These holes are definitely there to exhaust air out of the cabin as Nick said. Here was my solution. It involved RTV, contact cement, a toilet tank gasket, and 7 mil plastic:

Liberally use RTV to attach seal in place. Tape in in place temporarily:
http://dmctalk.org/attachment.php?attachmentid=38378&d=1449363050

After the RTV cured:
http://dmctalk.org/attachment.php?attachmentid=38379&d=1449363189
This seal is thick enough to direct most water travelling down away from the hole by itself

Contact Cement on the face of the gasket to glue the plastic cover:
http://dmctalk.org/attachment.php?attachmentid=38380&d=1449363467

7 mil plastic secured at the top 1/3, still allowing air to vent out from the inside:
http://dmctalk.org/attachment.php?attachmentid=38396&d=1449445097