'74 bus, carb leaking

Carbs & F.I.

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whc03grady
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'74 bus, carb leaking

Post by whc03grady » Mon Oct 01, 2012 11:30 pm

I opened the garage door to the near-overwhelming smell of petrol. Under the bus, passenger side, was a nice fresh pool. It seemed to emanate from the carb and not the line. Up up up the carb I looked, trying to find the point of highest egress. It was dripping off the low end of the arm for what this diagram unhelpfully implies is called "pump"; the low, bent end of 44 in other words but gas doesn't run through there so it's coming from somewhere else, right?

Clamping the gas to that carb stopped the dripping. The general area tidied (removed the air filter stuff) and cleaned up, I had my better half turn the key to 'on' to get the electric fuel pump running--fuel line unclamped now of course. Drippity-drip-drip gas was almost running out of...somewhere...not clear to me where. Key off. Carb off. The intake manifold was brimming with gasoline like a mug of coffee filled by an overenthusiastic waitress.

Okay, okay, I took the carb off and got gas all over the place even though I was holding it vertically. I called Halsey (it's past time when any but a West Coast shop would be open, see? And I know that name "Halsey" from all the scuttlebutt around here) and he said the waitress is prolly the float valve overenthusiastically stuck open, so I should take the six screws off the top of the carb and have a look. "Six screws? There're only five," I said but didn't argue further with Halsey, who was quite insistent. Maybe six is his lucky number. He also told me that aftermarket fuel pumps are more than happy to destroy float valves, which can "barely take 3 psi", what with their whopping 6+ psi and all. His advice on that point: install a 2 psi pressure regulator. As this problem didn't rear itself for ca. 1,000 miles with this pump and these carbs (or for ca. 13,000 miles with this same pump and a Weber regressive), I'll sit on this nugget until told otherwise.

It came off easy even though I only removed five screws--I used my imagination to remove the mysterious sixth for good measure--and the float looked fine. The float valve looked happy too, not backing out or anything. Muir shares a story in the Idiot Book about a similar situation where he managed to blow air through the float valve even holding the carb upside-down; I didn't have the same experience and can only get air through it when upright. Given Muir's surprise at his ability to get air through the upside-down carb, I assume mine was the desired result. Other advice Halsey and Muir independently offer is to knock on the top of the carb, more precisely on the top of the float bowl of the carb, with a plastic screwdriver handle to try to unstick the valve. I'm past that point.

Not quite sure where to go next I figured why not just put it back together? On went a new carbtop gasket (they sure don't seem to try too hard to get all those holes to line up with the holes on the carb, do they?). On went the carb. Again with the better half and the key and no leaky leak!? Hmmmm. My luck is never that good, plus wtf in the first place? I pushed the butterfly open and no gas is running down into the lower part of the carb--that's where I'd see something like that happening, right? The pump ran for a nice long while, and nothing.

Naturally the 1-2 valve cover is full of gas so that's another mess I cleaned up. The oil too--I almost forgot that one. What a disaster that would've been. (A curious thing when I drained the oil: At first, for a while, it's clearly just good ol' oil. But just as I catch myself thinking, "Well this is a waste of some 500 mile-old 20W-50" out runs gas gas gas. So I think that it's because gas floats on oil; naturally the gas would come out second. But then, it switches back to plain oil again. Huhn.)

It all got put back together, except the air cleaner stuff, because I'm gonna check in the morning and see if it's decided to start leaking again (i.e., the whatever's wrong in the carb is wrong again). Is that a decent line of thinking? I didn't put any oil back in it because what's the point if it leaks again, or so goeth my reasoning.

Thoughts? Observations? Criticisms? What parts do I need to get on deck?
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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whc03grady
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Re: Carb Leaking

Post by whc03grady » Tue Oct 02, 2012 10:07 am

This morning: No gas filling up the carb, no leaks that I can see, no strong gas odor. Some fresh Quaker State 10W-30 went in (we might get snow tonight; hot weather oil season is over) along with a new filter. It took some cranking to get started but did start. And ran, fine. I let it idle for maybe 10 minutes and shut 'er down. Looking in the carb after, and there doesn't appear to be any dripping or filling.

A phone call to a different place told me that maybe a chunk of crud got stuck in the float valve and held it open. They also suggested that a pressure regulator was a good idea, but doubted over pressure had killed the valve. FWIW.

Still soliciting opinions.
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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BumbleBus
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Re: Carb Leaking

Post by BumbleBus » Tue Oct 02, 2012 12:23 pm

Oh man.. I'm going through a similar thing. Gas in oil... but not anymore... but then again for a few days... then nada. Starts and runs excellent for a week, then dies every two miles. I'm abso-smurfly positive it's my carb at this point [Solex 34 TCIC prog], but the "rebuild" kit I got for it doesn't even come close to looking like it's correct. My problem is I've become emotionally attached to this carb for some unexplained reason and it appears to be rare [in the 'I can't find anything on the internet about it' rare]... I want it to run. I want to rebuild it. I want... not very Buddhist of me I'll admit.

Do let us know if you find the exact issue. I think I'm gonna take mine completely apart this winter if only to learn the bits and baubles. Good thing to do during the dark times when watching endless movies waiting for the next Montana summer.

PS - You still have that Weber for sale? I'm thinking 'stop gap' for Bumble until I can get some 36 dells or OG PICTs.
'72 Sierra Yellow Campmobile

I'd rather have a bottle in front of me than a frontal lobotomy.

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whc03grady
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Re: Carb Leaking

Post by whc03grady » Tue Oct 02, 2012 12:35 pm

Yes, I still have that Weber for sale but am loath to sell it to someone I know, even virtually, much less someone I might actually run into someday. You know it's garbage right?

But, PM sent.
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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BumbleBus
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Re: Carb Leaking

Post by BumbleBus » Tue Oct 02, 2012 1:20 pm

whc03grady wrote:You know it's garbage right?
Yeah... but if it "works" it's already better than what I got goin' on. Heh, heh. I'll mull it over. Thanks for your honesty. Amazingly a local shop in the Flathead here that I just talked to has a dualie OG Solex PICT setup from someone else's '72 that just needs a rebuild. We then started talking about rebuilding CB000076 at that point. Now I just need $3,500... ish. Hmmm. Winter is a good time to save & spend I suppose. I'd love to have a 0 mile 1.8 by next summer. The guy comes pretty recommended from some other local air heads, but was trying to pitch me on a redline weber setup instead :pukeleft: some "expert". :sunny:
'72 Sierra Yellow Campmobile

I'd rather have a bottle in front of me than a frontal lobotomy.

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Amskeptic
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Re: Carb Leaking

Post by Amskeptic » Tue Oct 02, 2012 2:52 pm

whc03grady wrote:This morning: no leaks.
Good job, Mitch. That is what as known as a diagnosis and repair right there. I suspect that some dumb piece of crap got in there. Happens. Happened to me with the Road Warrior, except that I had the additional step of discovering that I had hydrostatic lock in #1 that stopped the starter cold. Had to remove the plug and shoot out a jet of compression stroke + lotsogas.
Good job.
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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RSorak 71Westy
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Re: Carb Leaking

Post by RSorak 71Westy » Thu Oct 04, 2012 9:29 am

The left side carb on my bus has also started to leak fuel into the engine while parked. I just put a fuel line clamp on it while parked. I just recently had the carb apart and its fabulously clean.
Take care,
Rick
Stock 1600 w/dual Solex 34's and header. mildly ported heads and EMPI elephant's feet. SVDA W/pertronix. 73 Thing has been sold. BTW I am a pro wrench have been fixing cars for living for over 30 yrs.

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whc03grady
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Re: Carb Leaking

Post by whc03grady » Thu Oct 04, 2012 9:50 am

If the following suggests a forum change, please feel free.

Thinking everything was in order, I started out on a trip today. It started a little hard and ran a little rough at first, but I blamed it on the suddenly cold weather (low thirties). But as I drove through town, it didn't get any better; no power, wanting to die at stops. I pulled into a big gas station lot to have a look. First thing I see is that the left choke wire has shaken off, presumably due to the shakiness of the rough running. I squeezed the terminal a little and slipped it back on. With the engine running, I can pull 1 and 2 plug wires off the distributor with no change in running (they did arc across though, so I think the cap and plug wires aren't implicated). Removing 3 or 4 results in extreme roughness.

I think, when that float overfilled everything on the 1-2 side, I got all the gas out of the manifold and head, but could it've fouled the plugs to the point where they don't spark? I gingerly drove home and pulled the rightside plugs. They look fine.

Another couple things I noticed: I took the horns (the black triangles that fit onto the air filter box and carb tops) off and 3-4 (left) side seems maybe a little gassy, like, gas has been in the vicinity of the carb recently. And, the choke isn't open. Right side (1-2), the choke is wide open and everything seems dry as a bone. Last thing: the connecting rod locknut on that side was loose.

WTF?
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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whc03grady
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Re: Carb Leaking

Post by whc03grady » Thu Oct 04, 2012 12:59 pm

How does one check the float valve?
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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grandfatherjim
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Re: Carb Leaking

Post by grandfatherjim » Fri Oct 05, 2012 7:15 am

The chokes should certainly be the same. Check if you have 12v at each with the key on, at which time they should both open. If you have 12v there and one doesn't open, time for a new choke.
Re: needle and seat leaks - went through this too, replaced float, needle, finally top half of carb, and each time thought the problem was licked, but no. The thing is that it happens randomly. The major problem is that the fuel can fill up a cylinder and lock up your engine. This can be really serious if by chance the cylinder on the opposite side happens to fire when you try to start the motor.
Finally I put an electric fuel shutoff in line between the filter and the fuel pump, so though my carb may not be perfect, I'm protecting myself whenever the key is turned off.
Jim

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Amskeptic
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Re: Carb Leaking

Post by Amskeptic » Sat Oct 06, 2012 8:32 am

whc03grady wrote: First thing I see is that the left choke wire has shaken off, presumably due to the shakiness of the rough running. I squeezed the terminal a little and slipped it back on.

I can pull 1 and 2 plug wires off the distributor with no change in running.
Removing 3 or 4 results in extreme roughness.
rightside plugs look fine.

3-4 (left) side seems maybe a little gassy,
1-2 choke is wide open and everything seems dry as a bone.
Looks like right side carb needs a choke adjustment/fast idle link adjustment.
Looks like right side carb needs a verification of fuel supply, starting with a check of the cut-off solenoid. Do not yank plug wires on a diagnosis before merely pulling off the solenoid wire for the side of the engine you are questioning (at your coil where we have the wires all organized).
ColinI'MbackINfuelINJECTEDbus
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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whc03grady
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Re: Carb Leaking

Post by whc03grady » Sun Oct 07, 2012 1:59 pm

Amskeptic wrote:
whc03grady wrote: First thing I see is that the left choke wire has shaken off, presumably due to the shakiness of the rough running. I squeezed the terminal a little and slipped it back on.

I can pull 1 and 2 plug wires off the distributor with no change in running.
Removing 3 or 4 results in extreme roughness.
rightside plugs look fine.

3-4 (left) side seems maybe a little gassy,
1-2 choke is wide open and everything seems dry as a bone.
Looks like right side carb needs a choke adjustment/fast idle link adjustment.
Looks like right side carb needs a verification of fuel supply, starting with a check of the cut-off solenoid. Do not yank plug wires on a diagnosis before merely pulling off the solenoid wire for the side of the engine you are questioning (at your coil where we have the wires all organized).
ColinI'MbackINfuelINJECTEDbus
I yanked the plug wires simply to see if that side of the engine was doing anything. It's pretty clear it's not getting any gas, that's why I'm suspecting the float valve. That, and that the float valve had a recent severe failure. Throwing new things into the mix makes my head hurt/spin.

Really, this is too much. I'm not giving up altogether, but we'll be looking at Subarus by month's end. We need to have a car we can depend upon while turning these cars into cars we can depend upon.
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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hambone
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Re: Carb Leaking

Post by hambone » Mon Oct 08, 2012 12:45 pm

Sleeping on it often helps. Don't loose th' marbles yet.
With a clear head, ruling out variables is easier. Panic gets ya screwed, ask me how I know...
Is there a shop or community there? We all need cronies to help. Auto-sangha, crucial.
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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whc03grady
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Re: Carb Leaking

Post by whc03grady » Tue Oct 30, 2012 10:22 am

Okay, I'm pretty much over my tantrum.

I took the carb top off to get at what I think was the problem.
Image

In this shot, I have the spring wrapped around the pin on the float. Why? Because when I took it apart initially, the whole thing sort of flew apart on me and I wasn't sure how to put it back together. I made a guess, and guessed wrong.

Image
After taking apart a spare carb, it was apparent that the spring in fact sits atop the pin, not around it. Duh, in retrospect. But still, weird that it made a difference--assuming that's what made the difference.

Everything's running pretty well now. New issues to be posted under a new topic.
Ludwig--1974 Westfalia, 2.0L (GD035193), Solex 34PDSIT-2/3 carburetors.
Gertie--1971 Squareback, 1600cc with Bosch D-Jetronic fuel injection from a '72 (E brain).
Read about their adventures:
http://www.ludwigandgertie.blogspot.com

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Amskeptic
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Re: Carb Leaking

Post by Amskeptic » Wed Oct 31, 2012 7:38 am

whc03grady wrote:Okay, I'm pretty much over my tantrum.
it was apparent that the spring in fact sits atop the pin, not around it.
Everything's running pretty well now. New issues to be posted under a new topic.
Yes, Mitch, that is a good call. Now build upon your Can-Do Spirit! Do not focus on the duh moment that got you here. Honest to Gawd, these cars are fun! easy to work on! a blast to drive! honest!
Colin
(but if Chloe's engine lid latch bites my little bald head one more time, it is off to the car crusher for sure)
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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