1966 leak in truck deck

[Marc W]

When I open the trunk after it rains I get a flow of water from these two holes - large hole in the frame at the back of the trunk and small one at the front right. The water somehow gets in and pools in the frame structure and when I open it it pours out into the trunk. The trunk deck (sheet metal lid and frame structure) looks completely sealed all the way around. I've put new rubber insulation kit around the base of the trunk, and I've replaced the outer strip that goes from side to side at the back. I cannot see how/where water gets into the truck lid. Anyone ever dealt with this?

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[inspector]

The only opening is where the trunk lock penetrates the lid. Check for a proper seal.

 

[Frankie the Fink]

Yeah, on first gen Mustangs; particularly fastbacks. If there is an improper trunk seal it acts as a low pressure area for moving air (and rain) and the moisture is literally sucked in, even though a static test with a water hose may not show a leak.

First off make sure the trunk latch is adjusted for tight closure and then take a sheet of paper (or a dollar bill) and draw it along the top edge of the trunk gasket all the way around it should encounter friction over the complete circuit.

Of course some trunks are big enough that a person could get inside with a flashlight while someone sprays around the trunk lid gap with a water hose to find a leak source. THIS TAKES TWO PEOPLE - I don't think early cars had a mandatory internal latch release mechanism...

 

[mcm51]

Back in the day, we use to use a stiff dollar bill to check the rubber seal AND a lot of times that was the problem, but like Frankie said, I remember getting in the trunk of my '69 Torino with a flashlight and having someone closing the lid down and pouring garden hose water all around the lid, I found my leak real quick that way, in my case, it was the rubber seal at the top up near the rear window AND yes, through the years, I have seen leaks around where the key is mounted.....................

 

[Marc W]

When I open the trunk after it rains I get a flow of water from these two holes - large hole in the frame at the back of the trunk and small one at the front right. The water somehow gets in and pools in the frame structure and when I open it it pours out into the trunk. The trunk deck (sheet metal lid and frame structure) looks completely sealed all the way around. I've put new rubber insulation kit around the base of the trunk, and I've replaced the outer strip that goes from side to side at the back. I cannot see how/where water gets into the truck lid. Anyone ever dealt with this?

The only opening is where the trunk lock penetrates the lid. Check for a proper seal.

Thanks - When I went out and looked at the lock, it looks like there's no seal at all. going to buy a new seal and try it out.

 

[Thunder rd]

When I open the trunk after it rains I get a flow of water from these two holes - large hole in the frame at the back of the trunk and small one at the front right. The water somehow gets in and pools in the frame structure and when I open it it pours out into the trunk. The trunk deck (sheet metal lid and frame structure) looks completely sealed all the way around. I've put new rubber insulation kit around the base of the trunk, and I've replaced the outer strip that goes from side to side at the back. I cannot see how/where water gets into the truck lid. Anyone ever dealt with this?

To check seal on trunk gasket . Put a small bead of compound or some thing like that mustard might work through an old condemn bottle on top of gasket close trunk . Open trunk you will see where the bead is smashed or not there is youre leak . Fixing it may be another story. Thunder road auto body.