So Much For "So Much . . ." Desert Heat!

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Amskeptic
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So Much For "So Much . . ." Desert Heat!

Post by Amskeptic » Mon Jul 26, 2010 2:02 pm

The big heat found me . . . after demurring on baking to death in 120* Death Valley, I embarked upon a pilgrimage to my beloved trapped Steinway in the much cooler Nevada.
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. . . through the Dumont Dunes and what I call my Shoshone Valley:
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It is a sea out here, an old evaporated sea with sea floor and sand dunes under the relentless sun. This place fills me with awe. It also can make you drink two gallons of water in a day without ever having to pee:

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I took it easy on the BobD, but I also had come to realize that those prior ridiculous temperature readings Had A Cause. Here is the middle of the valve cover:
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It was the valve covers that tipped me off. The Road Warrior always had cooler leading edges, around 235* or so, and as you would go to the rear edges, the readings would be closer to 250* even 260*.

But the BobD had leading edges at 285* and I thought for certain there was Big Trouble brewing. The crankcase just under and along the pushrod tubes was 312*! It smelled hot but the dipstick was A-OK, hot but not unbearable. The taco plate was 240* The strainer plate, likewise, was 235-240*. The intake manifolds at the heads were 220* The exhaust pipes were no more than 650*, yet I remember the 850-900* I read off the pipes in the Road Warrior. So what was up?

Well, I had told Bob D to keep using his U-pipes even though the jackets had corroded away, but please take off the pipe wrap he had put on them. The pipe wrap would overheat the steel and allow rapid corrosion when storage condensation penetrated the wrap. "Bob, the jackets were just to keep exhaust heat in so the catalytic converter could reach operating temperature more quickly." I think I wrote that in the exhaust section of the book too.

Ahh, no. The jackets are a critical component for keeping exhaust heat away from the you know, crankcase along the pushrod tubes, the pushrod tubes themselves, the head surface facing the manifold, the cylinder barrels and the U-pipes are radiating enormous heat back at the . . . you guessed it . . . leading edges of the valve covers. I have elevated temperatures at everywhere the exhaust pipes blast the surrounding metal.

Vw could not have been happy to dispense with the prior shorter elegant heater boxes that cooled the pipes right out of the heads, and then have to come up with this meandering bunch of exposed pipes that head forward only to u-turn back to the late-style heater boxes. Major radiant heat, lemmetellya. But, I do not recommend wrap. I recommend proper aluminum jackets that allow air between the pipes and the jackets. Maybe small stiff aluminum dryer vent or water heater exhaust pipe tacked to the flanges, or sumpin'??

Anyways, once the engine itself was determined not to be the cause of those prior worrisome temperatures, I went ahead and flogged itfrom Baker to Barstow in the 118* heat up that nasty grade on I-15, and the engine really did not seem to care. It held 70 MPH with no protest, and it took the grade in 4th gear at 55-60. Our doomed Firestone Assassinator tires were not too pleased:
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"Deal With It" I sez:
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BobD - 78 Bus . . . 112,660 miles
Chloe - 70 bus . . . 206,845 miles
Naranja - 77 Westy . . . 129,490 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 91 Lexus LS400 . . . 94,225 miles

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Post by pj » Mon Jul 26, 2010 2:06 pm

Knowing that you will not admit it. Did you stop and have a blizzard? I can imagine in that kind of heat, ah hell who's kidding who? I find a blizzard quite comforting in any weather as long as I have my old man stretch pants on.

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Post by Amskeptic » Mon Jul 26, 2010 2:27 pm

pj wrote:Knowing that you will not admit it. Did you stop and have a blizzard? I can imagine in that kind of heat, ah hell who's kidding who? I find a blizzard quite comforting in any weather as long as I have my old man stretch pants on.
I couldn't give less of a damn to admit to all number of crimes, such as stopping at the Mad Greek Restaurant in Baker to purchase a strawberry shake with real strawberries and "real strawberry flavor" and I inhaled that thing. Two exits up, it exhaled itself.

I admit that I blew my nose in a paper towel that I accidentally used later to clean the driver's door glass. That didn't work out too good.

I don't have to tell you that I admit to driving with as much ventilation as possible. Makes for a casual contrast between me and the Suit in the white Cadillac Escalade. I admit that I prefer being on this side of that tinted glass.

I admit that seven days of desert heat and sand and sweat makes well-bathed people scurrying from their air-conditioned cars to their air-conditioned Temples of Consumerism look positively weird to me. That should wear off.
Colin :colors:
BobD - 78 Bus . . . 112,660 miles
Chloe - 70 bus . . . 206,845 miles
Naranja - 77 Westy . . . 129,490 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 91 Lexus LS400 . . . 94,225 miles

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Re: So Much For "So Much . . ." Desert Heat!

Post by dtrumbo » Mon Jul 26, 2010 2:55 pm

Amskeptic wrote:Maybe small stiff aluminum dryer vent or water heater exhaust pipe tacked to the flanges, or sumpin'??
Mine are missing (at my own hand) as well. They were rusted out and rattling so I cut 'em off. I'll measure the OD of the u-pipes (I've heard them referred to as "afterburners"?) and then I'll see what my favorite industrial hose supplier has to offer (Stainless steel high-temp flexible hose rated to 1000°).
- Dick

1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.

... as it turns out, it was the coil!

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Gypsie
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Re: So Much For "So Much . . ." Desert Heat!

Post by Gypsie » Mon Jul 26, 2010 10:54 pm

dtrumbo wrote: (Stainless steel high-temp flexible hose rated to 1000°).
Just reading that makes me tingle...
So it all started when I wanted to get better gas mileage....

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Re: So Much For "So Much . . ." Desert Heat!

Post by Amskeptic » Tue Jul 27, 2010 9:51 am

dtrumbo wrote:
Amskeptic wrote:Maybe small stiff aluminum dryer vent or water heater exhaust pipe tacked to the flanges, or sumpin'??
Mine are missing (at my own hand) as well. They were rusted out and rattling so I cut 'em off. I'll measure the OD of the u-pipes (I've heard them referred to as "afterburners"?) and then I'll see what my favorite industrial hose supplier has to offer (Stainless steel high-temp flexible hose rated to 1000°).
How do we get it over the pipe flanges? Can't cut it lengthwise and slip it over and re-"seam" it.

Those U-tubes are not afterburners, afterburn only occurred with the air-pump-equipped '73-'74 buses.

These pipes are called Radiant Convection Burners :flower:
BobD - 78 Bus . . . 112,660 miles
Chloe - 70 bus . . . 206,845 miles
Naranja - 77 Westy . . . 129,490 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 91 Lexus LS400 . . . 94,225 miles

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Re: So Much For "So Much . . ." Desert Heat!

Post by Sylvester » Tue Jul 27, 2010 12:21 pm

Gypsie wrote:
dtrumbo wrote: (Stainless steel high-temp flexible hose rated to 1000°).
Just reading that makes me tingle...
My Spidey Sense is tingling!
Up, up the long, delirious, burning blue, I’ve topped the wind-swept heights with easy grace. Where never lark, or even eagle flew. And, while with silent, lifting mind I've trod, The high untrespassed sanctity of space, Put out my hand, and touched the face of God.

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dtrumbo
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Re: So Much For "So Much . . ." Desert Heat!

Post by dtrumbo » Tue Jul 27, 2010 2:27 pm

Amskeptic wrote:
How do we get it over the pipe flanges? Can't cut it lengthwise and slip it over and re-"seam" it.
That's what I was thinking. Hopefully sometime this week I'll be able to order up the materials for the prototype.
- Dick

1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.

... as it turns out, it was the coil!

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dtrumbo
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Post by dtrumbo » Wed Jul 28, 2010 12:01 pm

So I measured my u-pipes and 2 1/2" diameter hose would provide a nice heat shield. However, the tingles-inducing stainless steel hose rated for 1000º isn't quite flexible enough. The minimum bend radius for the hose is 7.5" but the u-pipes have a bend radius of 3.75". A more flexible silicone hose had an acceptable bend radius, but is only rated to 500º. Colin measured 650º on the BobD and recalls 850º-900º on the Road Warrior. This won't do. Further, "re-seaming" a flexible silicone hose after it was split to slip over the u-pipes would be difficult at best.

I'll keep lookin'.
- Dick

1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.

... as it turns out, it was the coil!

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Post by sped372 » Wed Jul 28, 2010 12:36 pm

I'd like to help brainstorm but my T1 mind is having trouble envisioning this area... anyone have a photo?
1971 Karmann Ghia - 1600 DP
1984 Westfalia - 1.9 WBX

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Post by airkooledchris » Wed Jul 28, 2010 12:50 pm

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I believe this is the U-pipe in question.....
1979 California Transporter

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dtrumbo
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Post by dtrumbo » Wed Jul 28, 2010 1:08 pm

airkooledchris wrote:I believe this is the U-pipe in question.....
'Tis the one. It also has had the heat shield removed.
- Dick

1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.

... as it turns out, it was the coil!

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Post by sped372 » Thu Jul 29, 2010 1:38 pm

Wow that's some tight quarters.
1971 Karmann Ghia - 1600 DP
1984 Westfalia - 1.9 WBX

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sgkent
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Post by sgkent » Fri Jul 30, 2010 9:59 pm

Thank You -

Merlin The Wrench

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dtrumbo
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Post by dtrumbo » Sat Jul 31, 2010 6:18 am

Thanks sgkent! It looks like the non-HT model still has the temperature rating we need (1000º vs 1500º) and comes in a 3" size which would work. Now the only question left is how to get it over the triangle-flanges? I don't think splitting it is an option since it's a ceramic-cloth material with a helical steel spring. That would make it very difficult to "re-seam" back together. Hmmm... the wheels keep turnin'.
- Dick

1970 Transporter. 2015cc, dual Weber IDF 40's
1978 Riviera Camper. Bone stock GE 2.0L F.I.
1979 Super Beetle convertible.

... as it turns out, it was the coil!

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