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8,652 Posts
Discussion Starter · #1 · (Edited)
Last winter I got a small leaker getting the carpet moist enough that I'd have to leave the trunk to air out on warmer days. I figured to rule out the lid weatherstrip I'd have to remove built-up snow/ice from the equation and wait til just rain in the Spring. The leak 'improved' to the point where it flowed enough in all this rain that it just began to start smelling. With the carpet completely out I looked at the two other 'best bets' - the triangle welment at the hinge, and 'behind' the taillight. The shiny pointer shows the faint rusty trails and a bead of water in a small ledge. There was a large glop of factory body seal right above the stain:


Removing the taillight there's the same glop of putty, only bigger. I discovered what it's covering; and interesting archaic design body assembly tab. Extra care to gouge out all the filler as best as possible between seams of any joined panels:


Pullback shot for reference:


The area cleaned up inside:


All that was left is leave a tube of regular black silicone on the driveway to soften up and then, first 'pressure inject' as much as possible in cracks between joined panels, and then fill up the hole as much and as ugly as original:


8,652 Posts
Discussion Starter · #2 · (Edited)

My wife helped for a hose test with me inside and quickly noted an impressive additional leaker immediately above the first recaulked area.
The area is generally a seam of two sections, with the left portion as a simple flat connection using spot welds. The right section is just a part overlap without welds and the extreme right ending up a triangular gap large enough to easily slip a Q-Tip clean through to the inside. I looked at that point wondering why such a gap, but it might be to make sure the end area could never become a bind point when jigging and welding the mated panels.

Again, 15 minutes grinding, brushing and cleaning all original seam filler both outside and in. For the area on the left extra attention to gouging out all filler in the close connection between matching panels, even to the extent of wedging the panels apart with a chisel for extra cleaning and more gap to squeeze new silicone in. Then 20 Q-Tip's worth of acetone and cleaning all surfaces down to bare metal or clean paint for 'injecting' silicone from both inside and out. Between both sessions of repair I made sure to use the same volume of silicone as filler as had been dolloped in originally = ~1/5 tube total. And well, yes - no leaks now.


The trunk had a faint mildew/mold smell, but never got inside the cabin = good fortune. With the carpet out the trunk bed looked good. The carpet pad is in good shape with no sign of mold top or bottom, and the only visible mold anywhere was just on the cardboard backers under the spare cover, and on the pieces of an old pool float cut and laid in to protect the quarters. Spray mildew root killer and purple magic and all better.

[EDIT]: Knowing what to look for now, I just noticed in the fourth pic of my OP there's a faint rust line from the ledge above the area of my first repair. For all the hell I know, that could have been the sole culprit all along. Slowing brain.......or bad eyes...... I call both! 馃

8,652 Posts
Discussion Starter · #3 ·
3rd time's the charm? The hose test went well as reported, but running it only down the left side was clearly optimistic. A nice rain netted another big leaker, so flowing water on the right side of the backlite into the trunk ditch immediately showed a leak exactly the same location as my second post - other side. Same routine of gouging out the filler and thorough cleaning:


This shows the triangular void clear to the inside that's joining 3 panels:


All siliconed up and hopefully good for another quarter century:


Ugly yes, but emphasis on force-feeding caulk into the seam. And it's all covered up by the light.
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