The Goose: Converting back to Dual Solex PDSIT-32/34

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xyzzy
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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by xyzzy » Thu Sep 06, 2018 10:45 am

My original solenoids and the correct Pierburg 12v 55's seem to operate properly.. I have no luck whatsoever with the Borsol ones -- very intermittent behavior with them, and some arriving DOA. Cheap parts.

I feel like my bus runs about as good as I can get it. When Robbie gets back from his adventure I'll see if I can talk him into swinging by to take it for a drive and give his thoughts. I don't really have any other comparisons. The fast idle and chokes are a world of difference. The exhaust note on these carbs at cruise is almost harmonic. I've had multiple bus owners chase me down to tell me how good it sounds.

Bus has good power, drives great on the highway -- much easier driving 65mph now. I'm getting 14mpg around town which seems low, and a little better on the highway. Otherwise hesitation is only very slight at off-idle and most noticeable when it's cold/damp out. My LM2 doesnt give good readings at idle, presumably because I had the tip of the muffler welded back together after someone rear-ended me while parked in front of my house. At cruise the LM2 shows in the correct range 12.8-13.2...

I still need to:

1) Rebuild my brake booster -- it's still disconnected at the vacuum since the diaphragm was causing an air leak. Haven't had the time to deal with this yet.

2) Change out the fuel filter between tank and pump. I had one morning where during fast idle the rpms dropped and it chugged for a few seconds before dying. Started back up and it was fine. That fuel filter we didnt change during your visit and it has to have about 30k on it.

3) Install the fuel pump relay

4) My clutch pedal stopped returning all the way back up. I ordered a replacement cable, clevis pin, and bowden tube. The housing from the pedal doesnt look like it's been removed in a very, very long time, but the bowden tube looks newer. Bus still drives and shifts nicely, so thinking the cable/pin are probably just worn...

5) Do a smoke test
---
1973 Westfalia
Encinitas, California USA

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asiab3
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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by asiab3 » Thu Sep 06, 2018 12:13 pm

Check the bellhousing clutch arm return spring for cleanliness with regards to the pedal laziness.

What is your fuel pressure?

Always happy to hang out with your beautiful bus in person! I'll not have much to compare it to, most dual carb bus owners don't dig this deep and chase out every little demon.

Robbie
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by Amskeptic » Thu Sep 06, 2018 6:41 pm

asiab3 wrote:
Thu Sep 06, 2018 12:13 pm
A) Check the bellhousing clutch arm return spring for cleanliness with regards to the pedal laziness.

B) I'll not have much to compare it to, most dual carb bus owners don't dig this deep and chase out every little demon.

a) Pedal laziness can be any lack of lubrication in the entire system, especially the bushings at the lever assembly that bolts to the frame.

b) Not only happy to, but eager to drive it the next time I am in your area.
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: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by xyzzy » Mon Sep 10, 2018 6:07 pm

Aeromech hooked me up with a rebuilt brake booster. Very thankful! What a difference! It's so... civilized! Amazing difference in stopping -- I sent my toolbox flying when I applied the brake for the first time...

Next up: Fix the clutch pedal not returning all the way. This procedure sound about right?

1) Disconnecting the clutch pedal lever from the arm that goes to the housing (looks like one bolt?)
2) Remove the 2 bolts from the housing that mounts to the frame
3) Disconnect clevis pin and metal bracket thingy
4) Clean and grease everything.
5) Maybe some fresh paint on the arm and housing?

Do I need to disconnect the cable from the lever on the transmission between steps 2 and 3 to remove it?

I do have a new cable, clevis pin, and bowden tube -- perhaps best to just change the whole thing?
---
1973 Westfalia
Encinitas, California USA

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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by Amskeptic » Mon Sep 10, 2018 8:18 pm

xyzzy wrote:
Mon Sep 10, 2018 6:07 pm
Aeromech hooked me up with a rebuilt brake booster. Very thankful! What a difference! It's so... civilized! Amazing difference in stopping -- I sent my toolbox flying when I applied the brake for the first time...

Next up: Fix the clutch pedal not returning all the way. This procedure sound about right?

1) Disconnecting the clutch pedal lever from the arm that goes to the housing (looks like one bolt?)
2) Remove the 2 bolts from the housing that mounts to the frame
3) Disconnect clevis pin and metal bracket thingy
4) Clean and grease everything.
5) Maybe some fresh paint on the arm and housing?

Do I need to disconnect the cable from the lever on the transmission between steps 2 and 3 to remove it?

I do have a new cable, clevis pin, and bowden tube -- perhaps best to just change the whole thing?
Remove wingnut at bell housing lever.
Remove Bowden tube bracket from transaxle.
Disconnecting the clutch pedal lever from the arm that goes to the housing (looks like one bolt?)
Remove the 2 bolts from the housing that mounts to the frame
Disconnect clevis pin and metal bracket thingy
Pull cable right on out.
Clean and grease everything.
Reassemble and obtain 1" freeplay. It may take several applications of clutch to seat everything, so do recheck free play after exercising it.
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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xyzzy
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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by xyzzy » Thu Dec 20, 2018 10:10 pm

Thought I'd post an update since it's been awhile....

I've clocked about 8k miles since the big conversion back to the original dual solex carbs...

Today I did valves, oil and filter, ripped out a bunch of the AC hosing under the bus, and did a thorough cleaning before Robbie stopped by for a visit. We replaced all of the fuel lines from the tank to the carbs, and replaced the Carter P60504 fuel pump (with inline filter) and the mess of fuel lines and plastic filters (one before and one after the pump), one of which had around 40k on it.

We quickly found out that the replacement fuel pump (wrong part number) had 3/8" input, which of course was a no go for the nice 1/4" gates barricade I had purchased. After accidentally braking off the output nozzle of the original pump which was pretty brittle, I had 90 minute drive around town trying to find 3/8" fuel hose and a horrible hack job of screw in barb fittings to reduce it to 1/4". We ended up with: 5mm from tank to plastic filter to 1/4" barb fitting screwed into a 3/8" barb fitting to 3/8" fuel hose to the pump, and 1/4" gates barricade from the output of the pump filter to a plastic filter to 5mm hose to the original metal-tee to the carbs.

The new pump was registering less than 1psi on Robbie's known-good gauge. Odd. The pump, which I bought off Amazon mistakingly thinking it was the same one, is a *Carter AC127205B Electric Fuel Pump (Universal Rotary 2-4 Psi Bulk for VW Beetle)*.

I ordered the correct P60504 pump to fix the fuel lines again after the holidays. Plan will be 5mm from tank to plastic in-line filter, gates barricade to pump, gates barricade from pump, to plastic filter, and finally 5mm braided hose to carbs. We will also install a nice fuel-pump cutoff switch which Robbie wired up for me while I was barb-hunting around town -- and is now ready to install.

Otherwise, my MPG is still a little low (13 around town, 16 highway), there's still an ever so slight "studder" at very light throttle, but I'm being pretty picky, it runs and sounds great.

Image

Left to do:

1) Clutch Cable Return Spring (need to find one of these)
2) Remove AC unit from under dash
3) Remove road-kill-and-Colin-grater AC unit from under the bus
4) Finish removing the remaining AC hosing and two wires running from back to front
5) Find a new Westfalia top rubber seal -- the original one on the bus has the metal liner inside the gasket rusted out and it's started to peel away in two spots.
6) Replace the rear cargo seal
---
1973 Westfalia
Encinitas, California USA

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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by Amskeptic » Fri Dec 21, 2018 11:39 am

xyzzy wrote:
Thu Dec 20, 2018 10:10 pm
Thought I'd post an update since it's been awhile....

I've clocked about 8k miles since the big conversion back to the original dual solex carbs...

I ordered the correct P60504 pump to fix the fuel lines again after the holidays. Plan will be 5mm from tank to plastic in-line filter, gates barricade to pump, gates barricade from pump, to plastic filter, and finally 5mm braided hose to carbs. We will also install a nice fuel-pump cutoff switch which Robbie wired up for me while I was barb-hunting around town -- and is now ready to install.

Otherwise, my MPG is still a little low (13 around town, 16 highway), there's still an ever so slight "studder" at very light throttle, but I'm being pretty picky, it runs and sounds great.

Left to do:
<stuff>
Hey, a visit from the long-ago past, I remember sunshine . . . . . please note that the specified fuel pressure for a dual carb bus is 3-5 psi.

How did you work out the ignition timing? Do you have 28* BTDC at 3,400 rpm centrifugal, and if yes:
a)what is idle timing with no hoses
b)what is idle timing with hoses
c) what is maximum advance with hoses?

I need to drive that bus . . .
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: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by asiab3 » Fri Dec 21, 2018 7:28 pm

True, the fuel pressure needle on my gauge quivered up towards 1psi but never quite reached it, even when we removed all the filters and bled the air from the test line. The same gauge reads 2.5psi on my mechanical pump with or without any fancy hose bleeding.

From memory, the mechanical advance maxes out at 28°BTDC.
a) idle jumps up from pulling the retard hose and activates the mechanical advance to about 20° BTDC. Static timing showed about 6° BTDC.
b) 12° ATDC
c) 40° BTDC

I recall the numbers because the Geometrically Correct Itinerant-Air-Cooled Hand Painted Timing Scale told me so.

In neutral, when xyzzy held the throttle down to the point that always causes the stutters, the engine reached approximately3,000 RPM, so not much throttle plate opening. It's almost like there is a problem changing from the idle to main circuit, though I'm not as well-versed in the actual circuitry of these carbs as xyzzy.

From the passenger seat, the car seemed reeeeal smooth on the chokes, but the slight jitters did show up at very light throttle after a minute of driving. xyzzy, how was your drive to the beach on this cold and humid morning with the new starting procedure?

May the vehicles taking your family on holiday travels have better fuel pump nipples than the brittle plastic of yesterday, especially if you're going to take credit for breaking it. :)
Robbie
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by Amskeptic » Sat Dec 22, 2018 7:34 am

asiab3 wrote:
Fri Dec 21, 2018 7:28 pm
A) timing numbers
the Geometrically Correct Itinerant-Air-Cooled Hand Painted Timing Scale told me so.

B) when xyzzy held the point that causes the stutters, engine reached approximately 3,000 RPM, almost like a problem changing from the idle to main circuit.

C) From the passenger seat, the car seemed reeeeal smooth on the chokes, but the slight jitters did show up at very light throttle after a minute of driving.
Robbie

a) All good, right? Did you check timing flash at all plug wires at the "stutter point"?

b) you can see/hear the transition with the central idling circuit's air intake removed. Of course, removing the central idling air intake causes its own slight lean-out. The process is as follows:
If you hear the desperate suction at the central idling circuit, that is telling you that the vacuum retard is still on strong and the primary air flow is coming in through the CIS
As the left throttle plate dips below the retard nipple, you get more air past throttle plates than the CIS, and as importantly, you get a fairly immediate jump in timing from 10* retard let's say, to a good 20* advance. The only way to smooth this transition out is to *figure out the change in mixture* from CIS air stream to carburetors air streams.

c) evidence of lean carburetors as chokes open. Classic behavior for mid 70's automobiles trying to meet emissions.
(experiment, xyzzy, if it doesn't annoy the carbs, just for fun, get engine warm, crack loose the carburetor cut-off jets barely a 1/16th-1/8th turn. Does warm engine now exhibit similar smooth behavior as when cold?

I did not care about any weirdness of transition if engine was unloaded just sitting there while you rev it. I was only interested in dynamic behavior coming off stoplights. In that, the Road Warrior was a turbine in its latter years.
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: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by xyzzy » Mon Dec 31, 2018 7:41 am

FWIW, I've had the same light-throttle stutter with two different distributors, one is known good and works fine on another bus.

I noticed something today after replacing the screw-in-reducer barbs. When I run the fuel pump, there's air in the plastic filter immediately after the pump. It looks like the fuel is barely dribbling into the filter -- it's like 1/2 full of air......

Could these metal filters before the pump on the carter be obstructing this bad? It seems odd that the new pump does this too. Is there some sort of vent in the tank that could be obstructed creating a vacuum and preventing the proper flow?

Robbie: I got another brand new pump from Aircooled.net, maybe we should try removing the metal-filter connected to the pump and checking the pressure?

I also got some nice proper 1/4" to 5.5mm barbs so we could do a proper run from the tank, to nice barb, to gates barricade to pump, to plastic filter, to carbs....
---
1973 Westfalia
Encinitas, California USA

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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by Amskeptic » Mon Dec 31, 2018 6:00 pm

xyzzy wrote:
Mon Dec 31, 2018 7:41 am
FWIW, I've had the same light-throttle stutter with two different distributors, one is known good and works fine on another bus.

I noticed something today after replacing the screw-in-reducer barbs. When I run the fuel pump, there's air in the plastic filter immediately after the pump. It looks like the fuel is barely dribbling into the filter -- it's like 1/2 full of air......

Could these metal filters before the pump on the carter be obstructing this bad? It seems odd that the new pump does this too. Is there some sort of vent in the tank that could be obstructed creating a vacuum and preventing the proper flow?

Robbie: I got another brand new pump from Aircooled.net, maybe we should try removing the metal-filter connected to the pump and checking the pressure?

I also got some nice proper 1/4" to 5.5mm barbs so we could do a proper run from the tank, to nice barb, to gates barricade to pump, to plastic filter, to carbs....

Air in the filter is perfectly normal. If anything, it serves as a siphon break.

The distributor comment is not related to this particular issue at this particular time, except to say that a distributor normally does a huge timing transition so go find the carb issues as written above.
We have only hours to nail perfection in 2018.
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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xyzzy
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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by xyzzy » Thu May 23, 2019 11:27 am

Thought I'd post a quick update.

Robbie came over this morning, and we replaced my clutch return spring with a NOS one (thanks Robbie!!). We went ahead and changed out the cable and pin as it was worn. We also replaced my Dashpot as it wasnt quite engaging -- had a NOS Pierburg one which we trimmed the pin down to fit.

There is still the slight hesitation/surge? under very light throttle that's most noticeable when I'm driving to work through Leucadia at 30-35mph. Otherwise I feel like the bus runs best here where I have it. I'm definitely richer on the carbs and less on central idle then when Colin was here last year, and I'm getting 13.5mpg city, 16mpg highway -- which seems a little rich.

I have a backup newly refurbished 205J and vacuum can we can try to change out when Colin is here in August. All in all, I've been driving the bus everyday, and it just works.

There is a small bubbling rust spot under lower left corner of the the passenger side louvered window in the slider -- maybe we can address that when Colin's here in August as well.

Todo items for me are:

1) CV boots are torn
2) Rust spots under passenger louvered window in the slider
3) Remove the remaining AC hardware / road kill grinder / forearm grater
4) Undercarriage clean-up and undercoating
5) Take another shot at carb adjustments when Colin is here
---
1973 Westfalia
Encinitas, California USA

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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by xyzzy » Thu May 23, 2019 12:44 pm

Oh, I also had replaced the pop-top seal and the horizontal seal over the luggage rack. The original one had the metal clip liner thing completely rusted. Cleaned up nice, and the replacement from Bus Depot looks great.

When Robbie was here today, he asked about my missing rear pop-top seal. This had me confused a bit -- I wasn't aware there actually was one -- this is the "back" section of the westfalia top under the luggage rack. Is there supposed to be a seal?

Looking at an original photo of my bus (at the Grand Canyon circa 1975) it doesnt appear there is a seal on the back section -- only the big section that pops upward....

Image

Additionally, there are some rubber "spacers" underneath the mid-point on the sides of the rear section -- so I'm not sure how a seal would fit?

Current picture:

Image
---
1973 Westfalia
Encinitas, California USA

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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by asiab3 » Fri May 24, 2019 2:20 am

I sure don't see the seal in the Grand Canyon picture. But IT WAS THERE I TELL YA on some early Westy campers.

https://www.thesamba.com/vw/archives/ad ... US%201.jpg

It was my pleasure to help with the clutch work and send your brand new dashpot across the driveway in three pieces when the Dremel wheel shattered.

Change 'yer gear oil too, Mr.
Robbie
1969 bus, "Buddy."
145k miles with me.
322k miles on Earth.

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Re: The Goose: Converting back to Dual Solex PDSIT-32/34

Post by Amskeptic » Fri May 24, 2019 8:13 pm

xyzzy wrote:
Thu May 23, 2019 12:44 pm

When Robbie was here today, he asked about my missing rear pop-top seal. This had me confused a bit -- I wasn't aware there actually was one -- this is the "back" section of the westfalia top under the luggage rack. Is there supposed to be a seal?


1973 photo ... with commentary.
Colin

Image
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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