Vapor Barrier Replacement

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Vapor Barrier Replacement

Post by Amskeptic » Thu Dec 30, 2010 2:02 pm

These cars are very sensitive to water incursion through the doors. You can see water pooled along the wheel arch gutter after a good rain. This water makes short work of the door panels, particularly the replacement TMI panels made from cheap compressed paperboard.

You WILL need a full day for each door should you decide to perform the deluxe version below.

1) Remove the window crank handle. Please be methodical and gentle with the plastic cover. 90* from the plane of the handle you can pull the plastic away from the round hub, then gently twist it aside to uncover the screw.

2) Remove the door pull. Is yours broken? Thanks are due to the last person who over-tightened the screws. OEM buses will have little foam pads glued to both ends. Remove a screw while holding its end flush against the door. Then arc the outside edge out while unhooking the inside of the end from the sheet metal. An inadvertent yank here will break the plastic hook or crack the end.

3) The door pull has a plastic cover inside the well, pry it out carefully from the leading edge to access the escutcheon retainer screw. OEM buses have a small rectangular metal washer to distribute the tightened screw load against the escutcheon . Pull the door pull out a little and slip escutcheon free.

4) Remove speaker if so equipped. Remove the two screws on either side of the ventilation duct at the rear of the door on the later FI buses. They have little plastic caps that you pry off gently so they don't SPLIT. The screws have very specific shapes, so don't go losing them or the plastic caps will either not go on or fall off your replacement screws

5) Place the air extractor knob in the center of its slide. Grab your plastic spatula (it is on the stove next to the wisk) and pry the panel out along the top edge just under the vent window. Get near the clips before you pry and do not get impatient. Place spatula within reach on dashboard if you need two hands. Work from the top and front and release clips straight back. If you shift the panel or otherwise spaz out, their position will shift robbing you of orientation when re-installing.

If your panels are warped/water-damaged, hold on here. You are looking down between the panel and the door. You can see the inside view of the clips going into the door. Grab your spatula and try to support the rotted cardboard as best you can as you pull the panel free of the rear of the door. Sometimes you can shift the panel at this point and let the panel slip free of any clip still stuck in the door. Do not tear the door panel or its holes under any circumstance. Look at the vapor barrier on your OEM 1972 > bus and you will see a flap on the inside to protect your extractor registers. Remove old vapor barrier.

6) Do your door maintenance tasks:
a- remove and clean/oil/grease door latch assembly. It is easier to remove if you remove the inside door handle and pull rod, so now is the time to....
b- replace the foam surrounds at the window winder and door pull and fore and aft of the door pull rod support (see first picture for ugly new yellowish foam locations).
c- remove outside door handle and clean excess wax under the gaskets and oil the lock cylinder and door handle lever and spring.
d- remove any loose window felts and clean old adhesive from channels. Straighten felt as necessary, I swapped mine end-for-end for fresh new wear surfaces:
Image

My retaining clips (those horrible bleeders that also hold the outside brightwork surround and scraper) had ripped the rubber off the back sides of the felts, so I built up the rubber a bit with Permatex UltraBlack:
Image


e- clean the inside of the door insanely nicely. I used WD-40 and a terrycloth rag to laboriously remove every trace of adhesive on the inside surfaces of the door, and I cleaned the wax/undercoat from all inside surfaces of the door assembly down to within 1" of the lower s-bend course from the very front to very rear. Clean the bottom and drain holes with great gladness. Wax the inside door panel paint and buff clean. This WILL help the spray adhesive and help the door stay nice. Image

7) Once door panel is free, lay it down on a clean soft towel. Wherever you see lifted vinyl, clean underneath with GumOut carb spray on a paper towel, and clean the door panel where it is supposed to stick. Use Crazy Glue to spot-bond the vinyl that has lifted at the edges back onto the factory masonite panel. One little drop per flap at the corners, and a small drop every 1/4" as you slowly go around the perimeter will help stave off the day that you have to buy a new cheap soggy cardboard TMI replacement panel with its cheap glue that gives up in the mildest heat. Install new clips where yours are broken or missing entirely. Do check the bottom of the door cavity for any clips. Remove the stuck ones carefully from the door. Original clips are superior to replacement clips, so be nice to them. I ViseGrip all clips closed a little before installing them in the door panel so they have a sticky grip. Find their original orientation in the holes. They leave little dents where they live. You might also want to close down the "barbs" a tad on your new clips, they are too broad to fit in the horrid new rubber grommets which barely fit the holes in the door either.
Check the security of ventilation duct/armrest screws on passenger buses. Do not overtighten. They use dished broad washers to help center and distribute loads. Green LocTite would be a useful way to get low-torque fastening that won't loosen up. Many monkeys tighten these screws and break the priceless ventilation duct plastic where the screws go in. Hello. It is the cardboard crushing down that makes the ventilation duct/armrests get a little loose feeling. Tightening the screws past tight helps nothing.

8) Put on your thinking cap. You must think now. Shoo away the kids and the dog. Look at your LEFT door panel sitting on the clean soft towel. It's "inside" surface, the cardboard and the screws and clips are looking up at you. You need to make a new vapor barrier out of plastic sheeting (4 mil, minimum) that will be "more inside". On your new vapor barrier, you must make a new flap that will be "more inside still". Get your new sheeting laid out in a very approximate way over the door panel. Dimple the plastic sheeting (no perforations please!) with your door clips to set the perimeter. You can draw a connect-the-dots outline of the dimples about 1/2" outside each dimple and you will have a decent outline of the final vapor barrier. Measure the distance (red arrows) from the top panel clip holes down to where the barrier flap must be glued (purple and green) to the barrier:
Image

Take these measurements to your plastic sheeting and just rough in the glue line parallel to the top edge of your sheeting. "Borrow" an inch within the measurement (if it is eleven inches, for example, make a line at ten inches), to be your glue line. I used spray adhesive, so I had to put protective plastic over the barrier so it would not get spattered with glue.
I borrowed another inch (if the barrier flap is seven inches, cut to eight) and protected the flap from overspray as well.

Image

A medium coat of glue comes up very fast on smooth plastic. Allow to dry until tacky. Then apply the flap one inch gluey surface to the one inch glue surface on the barrier. Plastic likes to slide and slip, so make sure the surfaces are tacky before joining:
Image

9) If you're feeling lucky, punk, you can cut the perimeter of the vapor barrier to your drawn line. I do trim it down for easier handling but keep an inch for safety, and do the final trim on the door. Now you need to mask the window winder foam, the door pull rod and foam silencers, the door panel perimeter AND mask the air extractor AND mask the entire inside opening of the inner door panel. I threw in the towel. Image

So many people don't bother to prep and wonder why their windows always roll up dirty, and they wonder why the inside of the door fills up with crud and drains terribly, and the next time the panel comes off, the foam tears out. The BobD was a mess of WaxOyl smearing the window from the contaminated flap, and there was bondo and screws and washers glued to the inside of the door down at the drains. Your tape job only needs to cover a couple of inches away from the adhesive spray, it is not like primer that drifts all over the place.

10) Test fit your barrier and make personal notes of how you are going to work in the flap into the slot at the rear of the door as you negotiate major stickiness. Spray the clip perimeter and the painted surfaces of the door. Once tacky, pull the masking tape (and towel), fold the new vapor barrier at the glue line, and keep the flap away from contacting the sticky door. Start the flap into the slot at the rear of the door and insert above the extractor frame. Try to index the door clip hole just above the flap's rear slot with the corresponding dimple on the vapor barrier, work your way up to the top edge. Smooth out the vapor barrier from the middle to the outsides all the way around the door. It wants to be only sort of taut. There's a grooves on the inner door panel leading to a hole. Do not mush plastic into this groove and hole. Just let the barrier adhere across the surfaces below it:
Image

Here is what it looks like once the plastic has been proferred to the entire adhesive sprayed surface. I was a little bitty high on the glue line-at-rear-slot, but not enough to mess anything up. Use a fresh razor blade to trim the plastic to an exact perfect 1/4" past each grommet all the way around the door. Don't let the plastic bunch under the blade. Now you are going to join the ranks of the insane. You are going to puncture each door clip hole. The holes with good grommets, you are going to work the grommet edge over the plastic. I used a small screwdriver with a plastic spatula to work the plastic under the grommet:

Image

Shut-up. That's how they look from the FACTORY. In the above photograph, you can see a few grommets that I got the edges over the plastic. The holes without grommets, you can just stick new grommets in . . . Good Luck With That! Fully half of my new rubber grommets were too big/too dry/too hard. Help them get stuffed into the hole with a correctly sized phillips screwdriver up the middle to stretch them skinnier just a tad. Too much and you will poke a hole through them. Wax on the outsides of the rubber grommets may help. Don't want any more leaks? Make sure they are all intact and installed flush. A closer view of a successfully fluffed out grommet edge on the left, and the next one in line to the right. There are only sixty ninety billion thousand grommets:
Image

11) Lubricate each hole with a little Gypsie Vaseline. Double check the barbs on the new clips that you squished the "arrow tip" a little to help them enter the grommets. You want the panel to easily pop off next time, right? without tearing the cardboard?
Slip the air extractor knob into the grill of the door panel in your hand. Visually align each clip with its corresponding hole along the top. Make whatever little nudge-adjustments you need to, but keep them to a minimum. Once all clips are ready to go, start pressing each clip in. Maintain a resistance to gravity and start aligning the clips along the front vertical of the door with as little movement of the clips inside the cardboard holes as possible. Press in, one at a time. Finish the perimeter of the door. Reinstall your hardware. The window should be closed firmly, and the winder handle installed exactly horizontal, it will droop below horizontal when released.

A good careful job . . . will stop the leaks.
Colin

Image

ADDENDUM: the velocity of air that blasts through the air extractors on its way to the front door pillar vacuum was enough to keep blowing my flaps up, defeating the water-proofing purpose. Get thee some tinnerman nuts (those sheetmetal clips that allow you to screw a self-tapping screw through them) and trap the bottom of the flap to the door beam channel along the bottom. It adds to the experience to have a watertight bus:
Image

p.s.
Late model buses (post '76) have a nifty removeable grill!
Just grab your 3 or 4 mm allen wrench and LOOK up along the top inner surface of the grill. There are two tabs! Pull the tab down with your allen wrench and pull the top edge of the grill out towards you a little.

Image

Do the other tab too!
Image

With top edge out a little, pull grill upwards at one side or the other:
Image

Now you can pivot the grill up along the bottom and free of the door panel!
Image

SEE? Grill is off! So you can trap your new flap! (The older '72-75 buses do not allow you to pop the grill off - you have to remove the whole door panel and remove those nasty little retainers from the thin little plastic posts cast into the grill)

Image

When you are ready to reinstall, please hook the lower slots of the grill along the door panel edge. You may have to press inwards a little. Negotiate the grill louvre around the knob, and press down on the grill making sure that you have the slots of the grill actually engaged to the door panel. You can tell, because the lower edge of the grill will be flush-tight along the vinyl.

Do not attempt to "snap the top part into place". Especially after water damage, the cardboard will just cave under your press. No, get the EZ Allen out and pull the tabs down one-at-a-time as you push the grill in flush along the bottom and snick it in along top:
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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hambone
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Post by hambone » Thu Dec 30, 2010 7:01 pm

I swear this whole site is just a conspiracy to make me look bad.
AND I used a REALLY THICK trash bag for the vapor barrier.
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ruckman101
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Post by ruckman101 » Thu Dec 30, 2010 7:23 pm

Sheesh, I agree. I was just going to slap a layer of plastic on there at some point. My panel is safe from deterioration at the moment though, in the basement.


neal
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Amskeptic
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Post by Amskeptic » Thu Dec 30, 2010 8:54 pm

hambone wrote:I swear this whole site is just a conspiracy to make me look bad.
AND I used a REALLY THICK trash bag for the vapor barrier.
You early bus people can make any sort of barrier that actually . . . . . . . . works.

It is about . . . . . . what works.
I was Captain Ahab, and those leaky Road Warrior doors were my whales for over ten years. The air extractors added a whole new layer of weatherproofing technology to our cars. A flap. But not just any flap, a flap that had to be just so.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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ruckman101
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Post by ruckman101 » Thu Dec 30, 2010 10:09 pm

Actually, Hammie and I both have our moments of detail. I would have more, but this year was pretty consumed with mechanical concerns. I have to have some rationalization for being third on this tier.


neal
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Post by Highlander » Sat Jan 01, 2011 1:59 pm

Please forgive if this is a repeat, but when I have the door panels off I coat the backside of the Masonite/hardboard with two heavy coats of exterior marine spar varnish. The heavy duty stuff that is oil based. Yucky I know but IMO a bit better than water based sealer. I use cheap brushes for jobs like this and just throw them away vs. cleaning them with thinner.

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Post by Amskeptic » Sat Jan 01, 2011 6:32 pm

Highlander wrote:Please forgive if this is a repeat, but when I have the door panels off I coat the backside of the Masonite/hardboard with two heavy coats of exterior marine spar varnish. The heavy duty stuff that is oil based. Yucky I know but IMO a bit better than water based sealer. I use cheap brushes for jobs like this and just throw them away vs. cleaning them with thinner.
Does it dry to a hard finish? Still flexible enough to allow bending of the panel at next removal without cracking or splintering? Does it stay away from the glue holding the vinyl to the the cardboard?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Post by Highlander » Sat Jan 01, 2011 8:35 pm

Amskeptic wrote:
Highlander wrote:Please forgive if this is a repeat, but when I have the door panels off I coat the backside of the Masonite/hardboard with two heavy coats of exterior marine spar varnish. The heavy duty stuff that is oil based. Yucky I know but IMO a bit better than water based sealer. I use cheap brushes for jobs like this and just throw them away vs. cleaning them with thinner.
Does it dry to a hard finish?
Still flexible enough to allow bending of the panel at next removal without cracking or splintering?
Does it stay away from the glue holding the vinyl to the the cardboard?
Colin
Yes.
Yes.
Yes.

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Re: Vapor Barrier Replacement

Post by jackstar » Mon Feb 27, 2012 5:30 pm

Colin,

When I did my driver's door last week, I could not find good heavy duty plastic. So I went to the shower department of HD and bought a $5.00 clear plastic shower curtain and used that. Very durable and went on like a dream. Thanks for the tutorial.

Jack

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Re: Vapor Barrier Replacement

Post by Amskeptic » Tue Feb 28, 2012 10:47 am

jackstar wrote:Colin,

When I did my driver's door last week, I could not find good heavy duty plastic. So I went to the shower department of HD and bought a $5.00 clear plastic shower curtain and used that. Very durable and went on like a dream. Thanks for the tutorial.

Jack
Well that thar is initiative, boy, good on you. . . did it stretch correctly in curves and corners? so as not to do that evil little buckling thing where it invites . . . moisture . . . in . . .?
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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Re: Vapor Barrier Replacement

Post by Boxcar » Tue Mar 11, 2014 7:44 pm

Good Reading, even in 2014.
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Re: Vapor Barrier Replacement

Post by Amskeptic » Wed Mar 12, 2014 10:08 am

Boxcar wrote:Good Reading, even in 2014.
Someday, this website will be an efficient resource, and I will be too senile to even understand it.
"Nice write-up on the vapor barrier."
"I rode up on what barrier?"
"No, I said, 'nice write-up on the vapor barrier.'"
"Noah said what?"
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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WaterDawg
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Re: Vapor Barrier Replacement

Post by WaterDawg » Thu Jun 26, 2014 10:58 am

OK, got my door panels off, cleaned it inside and out - though it does not look like yours. :salute:

I understand the flap thing, but my concern is that I have a speaker ad I will need to cut the barrier to install it.

So do I make a pocket for the speaker to sit in on the barrier or add another flap.

I think either way, I may get a vibration in the plastic from the radio.

My water always comes in at the bottom under where the speaker is as well as the top of the dog leg.
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Amskeptic
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Re: Vapor Barrier Replacement

Post by Amskeptic » Thu Jun 26, 2014 9:49 pm

WaterDawg wrote: So do I make a pocket for the speaker to sit in on the barrier or add another flap.
Make the main barrier get trapped the speaker mounting flange. Modern speakers should have enclosures to protect the cone, or they should have a waterproof construction. If yours are open in the back, yes, you will have to make a "flap" that does not blow around in the substantial airflow that occurs in these late model doors.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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WaterDawg
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Re: Vapor Barrier Replacement

Post by WaterDawg » Fri Jun 27, 2014 5:18 am

I had gone ahead and just cut the bottom and two sides to create my flap.

If I still get water, it will only be able to drip out of the speaker itself and if that happens, I'll make a pocket.

By the way. I was "smarter" than you and found the sticky stuff auto makers use on most car doors for the vapor barrier.
Then I went to put my panel back on and found that the sticky stuff is too, umm, thick.

So looks like I'll be redoing one door and the other door will be done your way. :D

While I had mine all apart, I discovered evidence of previous body work ie dents that were pulled via welded posts. I went ahead and sanded, primed and painted these sections as there was some minor surface rust. My drain holes were wide open, but I also cleaned and washed the door as well and then used a shop vac in reverse to air dry it out along with the 80* temps.

I'm looking forward to a warmer, dryer and quieter bus.
Larry Jensen
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http://www.WonderofWander.com

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