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Need Help water leak source?? ideas

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Old Jun 8, 2013 | 05:59 AM
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Default Need Help water leak source?? ideas

We got about 3 inches of rain this week and the 78 did pretty well for being outside.

after the tropical storm I found the drivers side floor board was wet.

The drivers seat is dry and the firewall was wet in the area behind the brake pedal and outward toward the kick panel.

what is your best guess for a place to start looking for the source?

Thanks
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Old Jun 8, 2013 | 07:44 AM
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The seam along the top of the firewall, just below the edge of the windshield.
Did you look at the #2 body mounts? behind the kick panel.
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Old Jun 8, 2013 | 07:46 AM
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haven't done any investigation. only had the car two weeks

I will look at the mount and check that seam
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Old Jun 8, 2013 | 09:13 AM
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This is usually an indication you have a hole rusted in your windshield frame or a leaking windshield seal. (I'm hoping for the latter)

As sixfooter said... pull the kick panels out of the car and take a look in there for rust.. Large flakes means you have a serious issue.

I'm not trying to worry you... but if you take a look at this page it will tell you all about it.

It's a pdf so just click on "supporting document"

http://willcoxcorvette.com/repairand...lp.php?hID=306
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Old Jun 8, 2013 | 10:26 AM
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awesome PDF, I hope I am not in deep dodo here
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Old Jun 8, 2013 | 02:09 PM
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Originally Posted by oldschoolvette
We got about 3 inches of rain this week and the 78 did pretty well for being outside.

after the tropical storm I found the drivers side floor board was wet.

The drivers seat is dry and the firewall was wet in the area behind the brake pedal and outward toward the kick panel.

what is your best guess for a place to start looking for the source?

Thanks
Well I am going to sound real simple on this, as I also have to do this on the 82. You need to have another person with the water hose and you on the inside, and start at the top of the vehicle, holding the water hose in different locations for a specific amount of time at each location. You need to let it run freely and also under pressure. It will take some time, but I feel this is only the effective way to track down any leak, as water will run rather quickly from one place to another.
Also as mentioned, the windshield area, especially the wiper area, if there is any cracks or openings, that may also be a place where water is entering your Vette. That happened to me on a 75 that I had owned. Again it is more time consuming than anything else to locate the source.......

Last edited by 74 LS4-454; Jun 8, 2013 at 02:13 PM.
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Old Jun 8, 2013 | 02:12 PM
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Originally Posted by oldschoolvette
awesome PDF, I hope I am not in deep dodo here
great info....just have to locate the entry.....
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Old Jun 9, 2013 | 05:21 AM
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The weather came and got me yesterday, we got about 2 inches in 3 hrs. The car is wet again and now I got to dry it out and start over.


NEW DATA:

I noted water dripping from the dash area above the brake pedal?? I am sure this is a clue but of what I am not sure.
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Old Jun 9, 2013 | 10:11 AM
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Hopefully you have a hole in the firewall or the seam is loose. Doubtful... but I hope so.

If you do a water test as described above.. pour water right in on the edge of the fender and see what happens.
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Old Jun 9, 2013 | 03:37 PM
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Default Mine used to leak from the wiper-well area....

Once I finally figured it out I tried using "undercoating" to seal it. That didn't work very well...so I just cleaned the area all up, and then poured fiberglass resin into the little wiper-well and let it flow and find it's own low spots and level off. Haven't had a drip since and it's been 20+ years.
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Old Jun 10, 2013 | 12:23 AM
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Originally Posted by oldschoolvette
We got about 3 inches of rain this week and the 78 did pretty well for being outside.

after the tropical storm I found the drivers side floor board was wet.

The drivers seat is dry and the firewall was wet in the area behind the brake pedal and outward toward the kick panel.

what is your best guess for a place to start looking for the source?

Thanks
I had also leaks in my 78. I did the reverse to find the leak. I soaped up the outside and blew air in different parts under the dash area to see where the bubbles were forming. Works best with 2 people. I person outside looking for bubbles, and the other inside. I did not want to pour more water in than necessary. My leaks were from the panel seals.
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Old Jun 10, 2013 | 05:56 AM
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Originally Posted by Willcox Corvette
Hopefully you have a hole in the firewall or the seam is loose. Doubtful... but I hope so.

If you do a water test as described above.. pour water right in on the edge of the fender and see what happens.


Now I am a little worried. I got the car moved into the carport and am drying it out. I will run some controlled test today after work and post findings.

The fact is I will have to deal with it so I just need to find it. Hoping for a firewall leak. Expecting a rotted windshield frame.

That's my luck
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