Itinerant Air-Cooled Greetings From Pahrump II

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Amskeptic
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Itinerant Air-Cooled Greetings From Pahrump II

Post by Amskeptic » Sat Jul 26, 2008 10:12 am

It is hot, hot, hot. It is 105* and sunny. I have changed race. I belong now to a brown race.

My poor bus is misbehaving. I know not why just yet. The new fuel pump has been rattling ominously too. What is different about my bus THIS summer that would annoy a fuel pump to death?

At my dad's ex-wife's house (Charlene), I removed the engine to check out the endplay situation. What a situation, too. It read .007", which is just about .0047" more endplay than last July in Indiana. What I noticed was that two of the shims had sort of bonded with each other, thus increasing the shear speed between the thrust face of #1 bearing and the shim adjacent to it. Let's say I am doing 4,000 rpm at 72 mph. The thrust face is doing 0 rpm. First shim should be doing about 1,000, the next one should be doing 2,000, the next one 3,000, and the flywheel 4,000, right? These shims would not be stripping the oil film. But what if two of my German Supply $8.00 shims were cut/machined so roughly that they locked to each other? Then we would have 0 rpm thrust surface of the main bearing, 1,333 rpm against it with two locked-up shims, 2,666 at the next shim, and 4,000 rpm at the flywheel. That's if everyone divided the shear forces equally. But what I had was a great deal of shiny wear at the thrust surface of #1 bearing, and shims that did not look like they were spinning against each other. I had to sand them all smooth smooth smooth with 400 grit sandcloth, wash them carefully and then. . . oh then, yes, I had to figure out the real endplay with this toasted #1 thrust bearing that is moving in the case. I used five shims to make sure that the flywheel locked up against bearing, and found over .002" movement of the bearing inside the case. Ouch. Set the endplay to .0045" to allow for some of that reading to be the bearing movement, and the engine is sounding less thumpy. . . but.

Then I retorqued the left cylinder head with those Air-Cooled Net copper sealing rings. Wow. 7 ft/lbs initial torque. Then I painted a lot of tins that had been eaten by the road salt when I was in Rochester NY last Thanksgiving (I hate road salt). And put the engine back in the car with a Normandy Invasion of red ants going on under my back in the 102* heat.

So the fuel pump has always been here:
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Held on with a hose clamp to the diagonal bracket that helps support the fuel tank, it seemed a cool enough spot, close enough to the tank that it pushes fuel instead of sucks fuel. For years, it had been on the left side away from the starter. But after all of this rattling death, I moved it closer to the tank outlet over on the right, so I could route the fuel hose through the outside hole in the firewall where a wiring loom once travelled. This kept the hose away from the hot engine. Ran the hose into free air above the air filter intake where it tees to the carbs. But for some reason, rattle-o-death STILL happened. So, I took the opportunity to upgrade the heater outlets to '78-'79 bus style. I removed the bell caps from the heater valves:
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Then I attached 1 3/4" aluminum "pre-heater" hoses available from local FLAPS:
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And ducted them to underneath the bumpers:
Image
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And with my new muffler heat shield (obtained in Austin in April) finally installed 28 years after I jotted it on my "to-do" list, I thought, "this bus is now ready for more hot days." BUT. The damn fuel pump goes off into death rattle (vapor lock) AGAIN. So I re-positioned the fuel pump on the right side diagonal brace that welds to the torsion tube. Lots of relatively cool air there! BUT IT STILL DEATH-RATTLED! Now I am Officially Pissed.

This morning, (it is only 100* so far) I may have stumbled across the solution. I noticed that the heater valve, though fully closed, was still warming up the big black accordian tube near the new fuel pump location.
Yes, the actual flapper deal inside the valve has lost its little spring that keeps it firmly closed. I whipped up a little spring hook for the time being, to keep it pulled closed, and we SHALL see if it works.
Hot, hot, hot. I am off to replace the ball joints, it is going to be 106* today!
Colin
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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IFBwax
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Post by IFBwax » Sat Jul 26, 2008 10:53 am

Interesting Colin.. but again, why now? You didn't have any of this new set up last summer and it was just as hot right? What besides heat would cause the fuel pump strain and stress? Could there be a blockage in the tank? Could one of the hoses downstream of the pump have gotten kinked or restricted maybe because of the heat.. causing the pump to have to work harder to push the gas through?

All the best!!!!
The best navigators aren't sure where they're going until they get there. And then they're still not sure.

Frank Bama

http://www.partypickle.blogspot.com

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cheesehead
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Post by cheesehead » Sat Jul 26, 2008 12:27 pm

I have seen some people wrap/insulate the fuel pump; what do you think about doing that? But I am sort of with IFBwax could it be a fuel line that is becoming restricted from high temps does rubber swell with heat like that?
Good luck. It is Hot here in D.C with all the humidity! I just got back from 2 weeks in Alaska ahhh it was nice there. I saw a hightop bus going up the road in Denali N. Park yippeee

barrysmith
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Post by barrysmith » Sat Jul 26, 2008 12:34 pm

Maybe the general supply of gasoline is just shitty.

bus71
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Post by bus71 » Sat Jul 26, 2008 5:52 pm

It might be worth trying premium gas. It should be less volitile. My last time in Nevada, my bus really liked gas from Sinclair stations, it is a 71, however. I used regular and mpg was 2 to 3 better then usual. Genererly, gas all comes from the same source. Sometimes different additives are added at the tank truck, so? Good luck!

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tristessa
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Location: Uwish Uknew, Oregon
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Post by tristessa » Sat Jul 26, 2008 6:54 pm

Colin, is that one of those clackity solid state "Facet" pumps? It kinda looks like one but it's hard to tell...

I'm a fan of the rotary pumps -- Master/Airtex P/N E8012S is my preferred poison. Available at Kragen/Schucks/Checker/O'reilly as well as Autozone, Napa .. all over the place. Ran a used one with god-knows-how-many-hours-on-it in my daily-beater '65 Bug for four years, never a problem. Ran another one with the carbs on the Bus until I converted to FI in January, still using it as a feeder for the high-pressure CIS pump.

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Elwood
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Post by Elwood » Sat Jul 26, 2008 7:31 pm

barrysmith wrote:Maybe the general supply of gasoline is just shitty.
You know Im no expert on this ~ but I totaly agree with barrysmith on this.
Have done many miles in vws and truly believe that gas quality is the culprit in many cases of problems. I always put premium in my bus and have had few problems till I hit Oregon last spring. Just now getting back to normal with my known gas pump at local station. Not the milage by far you put on, but worth the mention. Think about it!
'69 weekender ~ Elwood

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satchmo
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Post by satchmo » Sat Jul 26, 2008 10:30 pm

Time to put the mechanical fuel pump back in?

Tim-still-has-original-73-mechanical-fuel-pump-working-nicely
By three methods we may learn wisdom:
First, by reflection, which is noblest;
second, by immitation, which is easiest;
and third, by experience, which is bitterest. -Confucius

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tristessa
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Post by tristessa » Sat Jul 26, 2008 10:41 pm

satchmo wrote:Time to put the mechanical fuel pump back in?
.. if the current case being used is one that can accept teh mechanical fuel pump, that'd be great. :bounce:

In my situation, neither engine I used the electric pump for had provisions for a mechanical pump. Bug had a 1776cc built from a was a mid-'76 AS21 case (EFI engine), the Bus engine is a solid-lifter 2.0L with an EFI case. So electric it had to be...

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satchmo
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Post by satchmo » Sun Jul 27, 2008 8:23 am

tristessa wrote:
satchmo wrote:Time to put the mechanical fuel pump back in?
.. if the current case being used is one that can accept teh mechanical fuel pump, that'd be great. :bounce:

In my situation, neither engine I used the electric pump for had provisions for a mechanical pump. Bug had a 1776cc built from a was a mid-'76 AS21 case (EFI engine), the Bus engine is a solid-lifter 2.0L with an EFI case. So electric it had to be...
But Colin's bus is a 73, so it should have the casting for a mechanical pump, unless he has changed cases at some point (probably not with only 550,000 miles :cyclopsani: )

Tim
By three methods we may learn wisdom:
First, by reflection, which is noblest;
second, by immitation, which is easiest;
and third, by experience, which is bitterest. -Confucius

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