Fixing water leaks into trunk on '70 Duster

[MopaR&D]

I found out a couple months back that water is leaking into the trunk of my 1970 Duster. Unfortunately it must have been happening for a good few years because I had (stupidly) taped down some cheap roll-up insulation in an attempt to reduce noise probably 8-10 years ago but it didn't work; upon removing the stuff a couple months ago I saw that what used to be a pristine trunk floor pan now has surface rust from water pooling and collecting under the insulation, I feel pretty dumb now lol. Shouldn't take more than a good sanding/wire wheeling and some rust converter to get it to stop.

Anyway I did some tests and it looks like the water is leaking in from around the bottom corners of the back glass; I removed the trim around that area and there is a bit of rust but it looks minor enough to hopefully repair without having to remove the glass. I think it's also leaking in through the screws that hold the glass trim on. Basically if I pour water over the rear window it starts dripping slowly from a gap in the inside steel panels near the trunk lid hinges.

Not to mention water leaking in from around the taillights but that seems straightforward enough to fix.

I'll post some pics after I get home from work so it's easier to see what's going on.

 

[MopaR&D]

Kept forgetting to grab pics but here they are. First two are the lower corners of the back glass. Third pic is looking up at one of the corners, you can kind of see the gap where water is leaking in and the fourth pic shows the surface rust on the trunk floor from the water dripping down.

 

[str12-340]

sorry to say it but I would guess that the back glass seal is leaking. I good glass guy can try to seal it without taking the glass out, but not if the seal is older and not pliable so they can get a gun tip between the glass and the seal. Good news is that a new seal isn't that expensive and you can cure any rust under the rubber when the glass is out. If you are going to trash the existing seal any way, you can cut the seal off the glass and take the glass out yourself, fix any rust and then pay to have it put back in correctly with the correct sealer.

If the trim clips are originals they should have sealer that closes the holes...

 

[MopaR&D]

sorry to say it but I would guess that the back glass seal is leaking. I good glass guy can try to seal it without taking the glass out, but not if the seal is older and not pliable so they can get a gun tip between the glass and the seal. Good news is that a new seal isn't that expensive and you can cure any rust under the rubber when the glass is out. If you are going to trash the existing seal any way, you can cut the seal off the glass and take the glass out yourself, fix any rust and then pay to have it put back in correctly with the correct sealer.

If the trim clips are originals they should have sealer that closes the holes...

Bummer, well good to know at least. I wouldn't be surprised if the glass seal is roached, it's originally a CA car and pretty much all the original rubber is toasted. I'll have to do some tests pouring water over different spots. I'm thinking of taking the car on a road trip to visit my uncle in NC (~4 hours) in the near future, any "redneck" methods for catching the water in the trunk before it gets all over the floor? Could just throw some disposable aluminum cooking trays in there lmao.

What's a good method for removing the glass seal? I have a 1970 Plymouth factory service manual, does that cover it well?

 

[str12-340]

rollup a couple of old bath towels and shove them into space above the wheel well outside of the trunk hinge. Check it often, keep a garbage bag in the trunk to put wet ones in and take some dry towels to replace the wet ones. Can you tell that I limped along like this before I fixed mine for good?