Drop off holes. WHY?

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Vinnie

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Hey guys n dolls,

When replacing my quarters I also replaced the drop offs, you know the flat sheet that goes down from the trunk floor?

Each panel has 2 holes in it. WHY? Why would you make holes in a panel that gets large amounts of water and spray and crap on it? Not to mention moist air creeping in.

I'm thinking of welding in patches. Are there any downsides of doing this?

Cheers,

Vincent.
 
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there are supposed to be 2 holes on the forward corners of them. They use some rubber drain valves. If water gets in the trunk, it will not stagnate on the lower quarters and rust the panels out, the water will be able to drain though the drain valves. The drain valves will also keep water and junk from coming in. I would keep them, I would not remove them. These are the drain valves:
 
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Hey guys n dolls,

When replacing my quarters I also replaced the drop offs, you know the flat sheet that goes down from the trunk floor?

Each panel has 2 holes in it. WHY? Why would you make holes in a panel that gets large amounts of water and spray and crap on it? Not to mention moist air creeping in.

I'm thinking of welding in patches. Are there any downsides of doing this?

Cheers,

Vincent.
There are typically gutters under the back window that channel water to the edge then drain into the wheel wells. So if you have them, your WW's would fill with water.
 

Vinnie

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There are typically gutters under the back window that channel water to the edge then drain into the wheel wells. So if you have them, your WW's would fill with water.
The rear window or the rear-side windows? My rear window is sealed in with no gutters. The rear-side windows I can imagine letting some water in coz they have crap sealing. I don't recall seeing gutters though...
Where exactly would those gutters be?
 
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No gutters on our cars. Water off the back window is supposed to drain around the channel under the trunk lid. The most likely place for water to get in is the rear lights. I always got water in the trunk after getting caught in rain (or washing the car). I "fixed" that by sealing around the bright aluminum and the body. I also sealed every other possibly spot that water could get in. The rubber drain valves also need to be kept clear, when they get blocked up, water can no longer drain.......... until a friggin big rust hole appears!
NPD ought to have them "Drain valve- quarter panel", but I only see 67-70 listed in my old catalog. I bought them there for my car in 2014. Check the website.
 

giantpune

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Yeah, I figured all that, but then, why would there be water in the trunk?
There could be a million different things that lead to water in the trunk. Anything from somebody not closing it all the way and it getting rained in to parts of the car failing like sheet metal rusting. Maybe the user trying to transport a fish tank in the trunk while driving on a dirt road. On my car, it has some rust pinholes around the trunk opening.

The person who designed the trunk recognized that stuff happens (tm) and those dropoffs would collect water.
 
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Interesting "gutter" design. These cars have a lot of water running though the inner panels when it rains, which baffles me. Last year I drove through a heavy rain storm during the HRPT and the drop offs were wet. I will guess that this excess water was the culprit. I had redone my trunk drop offs a few years back and added new drain valves. However, because I have some rags stored in there, they were all wet. I guess that the lesson learned is not to store anything in there that you don't want wet or anything that can retain water.
 

Vinnie

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Right. Though I'm not convinced about those gutters (bit far fetched imo and they could also just be there to strengthen stuff) I did only close the 2 holes closest to the rear and have left the ones right behind the wheel open for now.
 
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Didn't the left rear hole use a grommet for the fuel tank sending units wiring?
There is a second, slightly larger hole towards the rear for the sending unit harness. There should be a big panel grommet on the harness to plug the hole and insulate the harness from the sheet metal.
 

Vinnie

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Didn't the left rear hole use a grommet for the fuel tank sending units wiring?

o_O

Right, I closed one too many holes then, crap... Oh well, at least every bit of welding increases my skills...
 
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o_O

Right, I closed one too many holes then, crap... Oh well, at least every bit of welding increases my skills...
Live, learn. Lucky for me I am learning through your experience. I appreciate your sharing your question and all the responses.
 
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No gutters on our cars. Water off the back window is supposed to drain around the channel under the trunk lid. The most likely place for water to get in is the rear lights. I always got water in the trunk after getting caught in rain (or washing the car). I "fixed" that by sealing around the bright aluminum and the body. I also sealed every other possibly spot that water could get in. The rubber drain valves also need to be kept clear, when they get blocked up, water can no longer drain.......... until a friggin big rust hole appears!
NPD ought to have them "Drain valve- quarter panel", but I only see 67-70 listed in my old catalog. I bought them there for my car in 2014. Check the website.
Last night while looking under my car I noticed that these rubber valves on the drop offs were not sitting tight against the sheet metal. I figured that's how water got into my trunk last year while driving through a storm. That said, I think I will have to add a sealer or something around the edge to create a watertight seal, except the bottom edge. The idea is to leave the bottom edge open to allow the thin rubber seal to let water out. Is that how you installed it? With sealer around it?
 
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Last night while looking under my car I noticed that these rubber valves on the drop offs were not sitting tight against the sheet metal. I figured that's how water got into my trunk last year while driving through a storm. That said, I think I will have to add a sealer or something around the edge to create a watertight seal, except the bottom edge. The idea is to leave the bottom edge open to allow the thin rubber seal to let water out. Is that how you installed it? With sealer around it?
Actually Tony, I don't remember. I have two new ones I've been meaning to install as the older ones are getting hard. As for adding extra sealant around, I don't see that as a problem, it wouldn't need much. The problem with these is when dirt collect inside the trunk, it ends up as mud, blocking the openings. A periodic clean-out with a pic of some sort, might be a good idea........... as long as we remember to do it!!
 
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Actually Tony, I don't remember. I have two new ones I've been meaning to install as the older ones are getting hard. As for adding extra sealant around, I don't see that as a problem, it wouldn't need much. The problem with these is when dirt collect inside the trunk, it ends up as mud, blocking the openings. A periodic clean-out with a pic of some sort, might be a good idea........... as long as we remember to do it!!
I will add sealant 3/4s around it otherwise I can't see how they won't let water in through the edges - it can't hurt. I installed mine a few years back but they were not really tested until this really bad rain storm last year.
 
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