WHY does the targa leak?

[toml]

Hi all,

I have read all the posts on SM and all the SOGI tips about targa leaks, but i still can't actually work out why/how they leak.

Mine leaks from the front two corners of the targa, where it meets the car body. As far as I can tell, the water either pools up in the lower, plastic trim inside the car - or it just manages to run between the two rubber weatherstrips.

I've recently (last 7 days) pulled the whole thing apart, replaced all four weather strips, removed the targa side mouldings and re-siliconed them down, but I have made the leak worse (i didn't think that was possible).

Please, can someone explain how these targas leak, so I have some chance of fixing it. Sure, I could go crazy with silicone, but I'd rather work out exactly where the problem is and fix it properly.

Thanks.

 

[toml]

Forecast for Friday
16° A few showers.

 

[Nick M]

Hmmm. I haven't ever had one leak. But I suppose it is no different than windows or convertibles. The seal are old, new but installed incorrectly, or stuff added that shouldnt be there.

 

[toml]

Well my seals are now new and installed correctly (as far as I know).

I've sealed between the trim piece and the targa metal, but no silicone between the weatherstrip and the trim piece.

I don't know what else to try.

Oh, and the TSRM doesn't mention anything about a 'correct' method of installation.

 

[nissota]

If your car wasn't originally a targa and the targa roof was installed from another car without precise measurements :aigo: then there is a possibility that you will have leaks even though all your seals, weather strips are new.

I have seen this before on a car I was planning on buying, when the owner explained the problem, I continued the hunt.

 

[IJ.]

I siliconed mine on and this worked for a few years but after 400+rwhp it's leaking again .

 

[toml]

If your car wasn't originally a targa and the targa roof was installed from another car without precise measurements :aigo: then there is a possibility that you will have leaks even though all your seals, weather strips are new.

I have seen this before on a car I was planning on buying, when the owner explained the problem, I continued the hunt.

Errr... "installed a targa". How do you install a targa? Cut out the roof and bolt it on??

It's definately a stock targa top.

I don't understand -- some people seem to have no leaks, but no one really has any precise way to stop the leaks.


If the water is leaking into the bottom plastic moulding, how does it get in there?
If the water is just running between the two rubber seals (where they meet), how can I stop this?

 

[nissota]

Errr... "installed a targa". How do you install a targa? Cut out the roof and bolt it on??

Yes... this is done. targa roofs are transferred from wrecked cars.

Anyway I was just sharing an experience I had when I was looking for a Supra. The owner fixed the leak eventually by taking .375" from the column posts which allowed the seals to fit in the channel optimally.

 

[IJ.]

Must have been really nice to drive without all of the extra bracing Toyota installed in the Sills and Pillars! (NOT) :3d_frown:

 

[billspreston01]

the targa should fit pretty snug. I know I can't get mine to seat all the way down until I start tightening the bolts. Just make sure it's a pretty tight fit, and if it seems to be loose then who knows, maybe it was an original hard top, or maybe somebody took a few really really hard corners with the tarta off. Maybe it was in an accident and it's a little outta wack. My window seals leak right at the corners, so when I turn it streams in onto my lap.

Try and find out where exactly the water is getting into the car

 

[Rajunz]

This is why they leak. The trim pieces on the sides bolt to the actual top. The seals are doing their job, what happens is water leaks in between the trim and roof panel, and fills up the interior trim pieces with water. When you brake or turn a corner they empty out, usually on your lap or window controls. Pull them back off and silicone real good between the trim pieces and the actual top itself. This should solve all of your problems, it did on mine.

 

[toml]

Yeah it definately fits nice and tight.. I'm positive its a genuine targa.


I know the water leaks into the front corners of the targa, but I have absolutely no idea how it's getting in there.

Actually, I think it might be easier to diagnose if I pull one of the side weather strips off and experiment. Will try that in the morning.

 

[toml]

This is why they leak. The trim pieces on the sides bolt to the actual top. The seals are doing their job, what happens is water leaks in between the trim and roof panel, and fills up the interior trim pieces with water. When you brake or turn a corner they empty out, usually on your lap or window controls. Pull them back off and silicone real good between the trim pieces and the actual top itself. This should solve all of your problems, it did on mine.

Hmm that was my theory as to why it is leaking, but I did pull it all apart and silicone between the moulding and the actual targa top.

Maybe I didn't put enough sealant in there? I don't know, but it didn't help. Maybe I didn't seal in the right places.

 

[toml]

If you see Dylan's guide, this is how I layed down the silicone:
http://gallery.sanitylapse.com/v/supra/displayimage.php?album=140&pos=9

 

[Nick M]

new but installed incorrectly, or stuff added that shouldnt be there.

Is my best guess without seeing the car.

 

[toml]

new but installed incorrectly, or stuff added that shouldnt be there.

Perhaps what I should be asking, then, is "What is the correct install proceedure?"

 

[Rajunz]

That picture you showed of the caulking should be enough. At the side edges of the roof panel where the drip rail is, is where the leaks occur. Like I said water fills up the interior trim piece and then they spill out. Look at the side trim pieces are made and try to visualize how water could get into them.

I put new trim on mine and it leaked like crazy. I pulled them back off and caulked the back side like the picture and it solved all leaking. I also caulked around the screw holes.

 

[toml]

Mwuhahaha its fixed

Pulled the moulding off, put some decent primer + isolator on there, and re-applied the sealant in a different manner, making sure I sealed all the way to the edges.

It's been pouring with rain over the last few days and I haven't had a single drop of rain leak onto my lap.