Stupid Cowl-Plenum Drains

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Amskeptic
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Stupid Cowl-Plenum Drains

Post by Amskeptic » Sat Jan 26, 2008 6:30 pm

I cleaned everything nicely last spring when I resurrected the Frankenstein fresh air blower motor. But there appears to be no screen directly under the intake louvres, was there ever?

So when the carpeting got wet just six months later and I found clogged drain hoses yet again, I had to ask, why?

First picture shows the immediate vertical wall directly in front of the drain nipples. There is NO evident shoulder or stop to prevent you from cramming the hose through the nipple and against that inner vertical wall thus blocking the drainage pretty effectively:
Image


So, upon looking at the depth of the nipple, it seemed pretty safe to notch the lower radius of the drain hose a bit, to help water drain even if the hose is inserted against that inner wall:
Image

I did this notching with both the plenum drain hose and the cowl drain hose. The cowl has all kinds of nasty crap-trapping surfaces inside. I used simple weatherstrip adhesive to hold the hoses in place:
Image

Tristessa, any drainage issues in your experience?
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 93,996 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,113 miles

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tristessa
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Post by tristessa » Sat Jan 26, 2008 10:07 pm

I had a drainage issue shortly after we got the car, but clearing out the hoses took care of it and there hasn't been a problem since. They probably hadn't been cleaned out in 20+ years, what with all the crap I got out of there.

There should be a screen under the louvers. I'm pretty sure they were plastic, so it wouldn't surprise me at all to hear that some of them have disintegrated over the years. It's a rough-weave-looking plastic mesh. I've seen something very similar-looking the cross-stitch section of Michael's (craft store), only question is whether pieces available are large enough .. as long as you can live with white plastic.
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Post by Amskeptic » Tue Jan 29, 2008 1:56 pm

tristessa wrote:as long as you can live with white plastic.
NEVER!
How did VW expect people to clean that area out after a maple tree spring helicopter attack or a fall birch tree leave windstorm?
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 93,996 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,113 miles

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Post by vdubyah73 » Tue Jan 29, 2008 4:49 pm

Look for a fireplace screen in the metal pile at you're local dump/recycle/thrift shop. Just rattle can it black again. Cut with tin snips.


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tristessa
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Post by tristessa » Tue Jan 29, 2008 8:39 pm

Amskeptic wrote:
tristessa wrote:as long as you can live with white plastic.
NEVER!
How did VW expect people to clean that area out after a maple tree spring helicopter attack or a fall birch tree leave windstorm?
No idea how VW expected people to clean that area out.

If white's no good, pick up a spraycan of Krylon Fusion in gloss black. It's supposed to be some special paint for plastic.
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Post by Amskeptic » Wed Jan 30, 2008 12:11 pm

The top of the plastic plenum has its plastic mesh to protect the airflow into the interior. But the metal cowl space has only the slots below the windshield. So any screen has to secure to the slots, snugly, to prevent clogging the drain hoses. Any reliable ideas that keep the paint intact?
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 93,996 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,113 miles

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tristessa
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Post by tristessa » Wed Jan 30, 2008 2:19 pm

Amskeptic wrote:The top of the plastic plenum has its plastic mesh to protect the airflow into the interior. But the metal cowl space has only the slots below the windshield.
Then you've got all the pieces; that's the mesh I was thinking of.

I suspect that VW didn't think their cunning plan all the way through when they introduced that trunk-bulging fresh air system with the fan in '71. It's very very common to find rust-out along the top of that bulge in the trunk; a nice straight line right about where crap collects and holds moisture.

I know Kamei made some "scoops" to go over those vents back in the day, and IIRC the opening on them faces the windshield. Additionally, during the time I was at DDB we made a couple prototype sets of magnetic covers to go over the vents -- the idea was that they would keep leaves & crap out while parked, possibly also prevent water intrusion. I don't remember how well it worked out, just that it was a PITA to get the shape "just so" and that sheets of flexible magnet were kinda spendy since we were buying retail from OfficeDepot at the time...
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Re: Stupid Cowl-Plenum Drains

Post by hambone » Thu Aug 25, 2011 2:16 pm

And here I am 3 years later.
No screen below the slots? Weird. Yeah it's not a very good design. All it needs is access from the trunk.

I just read in the Bentley that you can't adjust the doors when the car is on a rack, too much body flex. I wonder if a diet of mountain roads would be bad for a flexy car.
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Re: Stupid Cowl-Plenum Drains

Post by Amskeptic » Sat Sep 03, 2011 4:58 pm

hambone wrote:And here I am 3 years later.
No screen below the slots? Weird. Yeah it's not a very good design. All it needs is access from the trunk.

I just read in the Bentley that you can't adjust the doors when the car is on a rack, too much body flex. I wonder if a diet of mountain roads would be bad for a flexy car.
Like any bug or kubelwagen, these cars do fine when taking the loads through the wheels up through the torsion bar tubes. On a rack, the loads are different. Suicide door Lincoln Continentals used to chip the damn doors against each other if you put your jack stands outboard of the suspension mounting points.
Colin
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 93,996 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,113 miles

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hambone
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Re: Stupid Cowl-Plenum Drains

Post by hambone » Sat Sep 03, 2011 5:24 pm

Avoid getting airborne!
http://greencascadia.blogspot.com
http://pdxvolksfolks.blogspot.com
it balances on your head just like a mattress balances on a bottle of wine
your brand new leopard skin pillbox hat

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hambone
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Re: Stupid Cowl-Plenum Drains

Post by hambone » Wed Oct 19, 2011 3:17 pm

That was awful. Couldn't get the vacuum cleaner to bend like a sodastraw zigzag, so I had to scoop the piles of needles, dirt, leaves, and debris with a screwdriver thru the air slots towards the small opening where the fresh air box goes. Then I had to get the compressor and blow the rest out of there, what a mess. About 1/2 gallon of stuff came out of there.
And then insane contortions to reattach those tiny screws, wayyyy up in the dark. Ridiculous.
http://greencascadia.blogspot.com
http://pdxvolksfolks.blogspot.com
it balances on your head just like a mattress balances on a bottle of wine
your brand new leopard skin pillbox hat

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Amskeptic
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Re: Stupid Cowl-Plenum Drains

Post by Amskeptic » Wed Oct 26, 2011 10:39 pm

hambone wrote:That was awful. insane contortions to reattach those tiny screws, wayyyy up in the dark. Ridiculous.
Yeah, ain't they a peach? Magnetic correct-bit screwdriver helps. And a chiropractor for later.
BobD - 1978 Bus . . . . . . . . . . .111,130 miles
Chloe - 1970 bus . . . . . . . . . . . 206,787 miles
Naranja - 1977 Westfalia . . . . . 93,996 miles
Pluck - 1973 Squareback . . . . . 55,510 miles
Alexus - 1991 Lexus LS400 . . . 72,113 miles

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hambone
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Re: Stupid Cowl-Plenum Drains

Post by hambone » Fri Oct 28, 2011 11:15 am

I dropped one behind the mini-bulkhead in front of the pedal cluster. Welded in place, but a gap at the top..."see you in Hell, screw!!!" Luckily I had another.
I seen'ed a SB at a wrecking yard with a hole cut in the trunk side of the vent-structure and a square of sheet metal screwed in place. Yep.
http://greencascadia.blogspot.com
http://pdxvolksfolks.blogspot.com
it balances on your head just like a mattress balances on a bottle of wine
your brand new leopard skin pillbox hat

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