Waterproofing my Speedster

Ok guys---tell me what I missed in waterproofing my VS. I undercoated:

1. All the bolts sticking out the bottom---looks like about 8-10 or so for the seats and seatbelts

2. The 2 holes behind the battery where the battery cables go through the firewall

3. The 4 bolts that appear to come from under the dash underneath the car----maybe 30" behind the bumper---up high from underneath the car.

4. Along both sides between the pan and the fiberglass

5. A 1/2" hole at the bottom of the battery box on the left side looking from the front

6. Where the brackets for the luggage compartment that hold the bonnet go through the firewall

7. Around the large, thumbscrew thingies that hold the battery down that stick through the bottom-rear of the battery box

8. "Frost King" weather stripping around the doors over the existing rubber wx stripping.

---Someone had mentioned to silicone around the windshield posts but that appears to be unnecessary when I eyeball it---there is a good rubber gasket under it

----That's alli I could see. I do have a seal ordered that goes on a real 356 Speedster to seal the top of the windshield with the top to eliminate the blue tape fix. It's not here yet--I have high hopes for this item. Some members are getting good results with this seal.

I WILL be dry for the Carlisle trip!! (Or maybe not as wet as I would have been so that's still a plus to me.)

So what did I miss? Many thanks-------Jack

On a CMC, at least, water can come in under the rear seat. There isn't a perfect match between the subframe and the pan there.

I did as indicated in the CMC manual and fiberglassed the body to the pan. First I filled voids with spray in foam and trimmed it flush.

Michael's right- that seam is the biggest impediment to making any pan based car (not just a CMC) weather tight. It's EXTREMELY difficult to get sealed up after the fact (I ran three tubes of caulk in "the crack" on my JPS, and it had been foamed).

Gordon's car is tight because Gordon put the body on the pan himself, and payed attention to the problem while it was exposed.

FWIW, sealing the trunk up may not be the best approach. I'd work on sealing off the hood hinges from the cabin of the car. You may want to look hard at how the tunnel is sealed up as well (mine leaked air badly out the shifter and e-brake boots).

Look at the CMC build manual - they have you use rubber around the hood hinges (does yours have the fiber box glassed in under the dash?)and also a rubber skirt in rear - just in front of the engine. That expanding foam stuff is great for any voids you find - it reduces road noise too. Dynamat could seal some of the very small seams too. Did you use the rubberized spray on undercoating or brush on (spray seems to go on thicker)?

........" Water proofing my speedster AND "I WILL be dry for the Carlisle trip".....
Great humor indeed, be sure to have a soap on a rope handy... you know, just in case. ~Alan

Stan's right - I mated the body to the pan myself and used six (6) big, contractor-sized tubes of clear silicon caulk where they mated. Had the beads built up to about an inch before I put the body on. Major squishing going on. Then I went back with a high intensity light and found any other voids left and filled them with more caulk (had this huge hole at the top of the tunnel at the front bulkhead). All this because I didn't re-use the now-petrified rubber gasket that came on my donor car. Probably better off without it.

Before you go nuts trying to fill voids you don't even know you have, find the ones you DO have by driving it in the rain. You may not have as big a job ahead as you may think (and then again....) especially after you sprayed undercoat everywhere.

At least driving it in the rain NOW will show you where the leaks are, and then you can devise a way to seal them. Clear or colored silicon caulk works great for most voids. If they're big, then either build up beads of caulk, or spray in LOTS of rubberized undercoat or "Great Stuff" spray foam works well, just be aware that it expands about 5X while it cures and has no structural strength when cured. It's also sticky as hell while it's curing, but is not sticky once the stuff dries. I don't know about how waterproof it is, either, especally if subjected to splashes.

The biggest leaks seen at Carlisle (in order of worst to least) were from the body to pan intersection behind the seats (thrown up from the wheels), Windshield header, poor WX stripping at the front of the doors, intersection of windshield corner and side window, at the rear of both side windows. Those are the majors. There are many other potential locations, but they tend to vary a lot from car to car. That's why it's a good idea to drive it in the rain NOW to find out where YOUR car leaks - they're all a little different.

Your fallback if that other header seal doesn't do the trick is to use Blue Painter's Tape like the rest of us. It may look a little weird, but the stuff works. Just rmember to set your latches so they pull together 3/16" to 1/4" after the header is seated on the seal. Road testing in rain or moderate pressure garden hose trained on it after that is prudent.

BTW: "Real" Speedsters leak almost as much as our cars ;>)

BTW: "Real" Speedsters leak almost as much as our cars ;>)

I hate that, because that is where my car drifts away from originality. ;-) Damn thing doesn't leak!

Jack, the most annoying leak I have is about 1/2" before the windshield post to the post itself.

Thanks to all---well I both sprayed and brushed the undercoat on. It's an aerosol 30M product and seems perfect for this job. I did learn that a second coat after the first one dries adds to the feelinmg that I really got that sucker sealed.

I'll look at that notorious seam between the pan and the body behind the rear seat--I haven't done anything there yet.

I got two cans of undercoat and two cans of Great Stuff and I've gone through one can of undercoat. Haven't used any Great Stuff yet. Maybe under the rear "seat".

I just didn't underatand the advice about the windshield post???

Wow--I have such an adversion to driving my car in the rain! But that's gotta be what I need to do now. I'm heading to Lowes for materials and will report back. --Thanks to all!---Jack

Dale:

You car don't leak??

What fun is THAT?? ;>)

Leaves you far less to complain about!

gn

Jack, I also had (I hope!) leaks at or near the posts. Found a syringe, loaded it with black caulking and filled those pesky hidden voids.

I chickened out and didn't drive in the rain for my trip to Lowe's.

Soon, very soon.

Great syrenge idea--I'll give that a try. Thanks!!--Jack

Hey Jack, they don't call our cars tubs for nothin' you know. I'm still fightin' pi$$in' gremlins in my coupe.

Soap on a rope and a bag full o' towels are standard equipment in my speedy.

You "Chickened out" in little misty stuff down there in Arkansas??

What a Whus!!

;>)

Guilty as Charged.

I still am finding places that will allow water in so I'll wait for the baptism until I'm sure I've done all I could.

BAAAAWWWW!!---Jack

Great Stuff works great; I used it uder the rear seat.

Don't make it too water tight. If you do that you won't have anything to stand around holding a beer and converse about at Carlisle. Consider leaks a badge of brotherhood.

I am done! Todat I lifted the carpet and found that the access plate over the tunnel for reaching the shift shaft was missing. I see a lot of members complaining about leaks behind the seat and this must be where the water comes from. I cut an aluminum plate to fit and
selaled it in with undercoat for a waterproof fit. Also on the VS there is an aluminum plate that loosely covers the area between where the access plate went and the area behind the seat. There was still a 1/2" space where it failed to fit to the floor so I waterproofed that with the Frost King weatherstripping. All that is left is to install the waterproof strip for the windshield top.

I know I will still have water around the side curtains butI feel pretty good about having filled so many spaces where water was sure to come in.

The car could have come from the factory waterproofed to this degree you would think.

Bring on Carlisle. I'm still hoping for nice wx for the drive though but I had enough misery with wet clothes and gear in the Marine Corps!!

---Jack

Jack, the waterproofer, wrote: "The car could have come from the factory waterproofed to this degree you would think. "

Personally, given the current state of affairs, I would never think that...

gn
(I still have my towel handy...)

BTW: Come back to Parris Island.....your friends are calling to you...

Jack wrote: "Today I lifted the carpet and found that the access plate over the tunnel for reaching the shift shaft was missing. I see a lot of members complaining about leaks behind the seat and this must be where the water comes from.

That missing plate is only the beginning. You are about 5 tubes of caulk away from even starting to fix all the places water can get in back there. Sorry, man.

Awwww....don't be too discouraged, Jack. You've already done a whole lot to seal it from the outside, and doing some of the stuff you've read about since should get you a long way towards dryness.

Still, the best way to find out if and where you need to seal more is by driving that puppy in the rain and then figuring out what to do...

Hang in there!

gn

Reading Jack's post I remember another thing that might contribute to getting water in and I noticed it was missing when I had to replace the nosecone in my tranny (remember the infamous "Gene Berg sump incident"?). I found out that the tranny was missing the rubber seal between the chassis and the nosecone; it's supposed to seal the area where the nosecone goes into the tunnel. I got it at my local VW shop and installed it when I replaced the tranny. This is a link to the part:

http://www2.cip1.com/ProductDetails.asp?ProductCode=C16%2D111%2D289B

Only $6.50 too.