Solex 34 PICT 3 and fuel pump questions

[livingskies]

It seems that there's always something new to make life interesting. Two questions for those more familiar with fuel pumps and the Solex 34 carburetor.

We tried starting the 1964 bus today - probably has not run for 15 or more years. Ignition sorted, with new plugs, points, condenser, rotor cap, etc, timing set, wiring checked out.

After installing a new in line fuel filter and replacing the fuel lines near the engine, I poured a couple of gallons of gas in the dry tank. On first turning it over, a loud scraping sound dominated. Turns out that was the fan in the shroud hitting the shroud. Fixed that by partial disassembly and reassembly - hoping it stays fixed. No idea why that situation existed, but is quiet now.

Motor turns over well, but no fuel pumped from the fuel pump to fill the new clear fuel filter. Primed the carburetor a number of times, but that did not help. The engine did fire a little from the fuel poured into the carburetor. Didn't spend too much time on this as quite sure the fuel pump was bad and the carburetor likely needed TLC after sitting that long.

Question 1 - New fuel pump time - about fuel pump differences for alternator or generator systems. On looking at the parts listings, the vendors sell fuel pumps for vehicles with alternators and fuel pumps for vehicles with generators. The only reason I can think of for this is that the alternator fuel pump may provide more clearance from the alternator for installation since the alternator is larger than the generator. This bus has an alternator. Is there another explanation that I'm missing, or is that all there is to it?

Also, I see that they offer pumps that use 4" pushrods and pumps that use 4 1/4" pushrods - this bus has a 4 1/4" push rod at the moment. Is there any reason why I could not buy a fuel pump that requires a 4" push rod and use that with a new 4" pushrod? No idea what year the engine is.

Question 2 - This bus has a Solex 34 PIC 3 carburetor (used from 1971-74) on it. I took it apart and cleaned out the dried on crud in the bowl and all the passages. There is one puzzling thing that the parts diagrams have not helped with. The carburetor has a 15 mm hole on the front face. All that covered the open hole was a loose piece of roughly cut thick plastic, held in place by a piece of twisted wire that would have let lots of air leak into the throat of the carburetor.

Am I correct that the hole should be well sealed with some sort of a plug? If so, I can make something up and seal it in place. Any other ideas of what to do with that hole. A picture of the hole below:

[tasb]

Yes a plug belongs there. I've seen a coin used in place of the plug, don't recall if it's a dime, nickle or quarter.
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1965 hardtop Deluxe Microbus owned since 1990 M 620 factory 12 v 1500cc

1961 (October)Single Cab- Road Trip Workhorse

[mdege]

The pushrod needs to match the pump. Either pump/rod combination will work. The space is tight between pump and generator/alternator. It can be too tight if you have an alternator. That is why different pumps are offered.

Depending on what kind of pump you have, you might be able to rebuild it.
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- Michael

1965 21F: Restoration of a former '65 firetruck
1963 Typ3 Notchback project
1988 Multivan Magnum 112i
1984 Standard: My son wanted a bug for his first car

[livingskies]

Thanks tasb and mdege for confirming these things.

I could not find a coin small enough, so JB welded a 15mm metal button into the hole.

The alternator and the four bolts that hold the front of the fan assembly were loosened off anyway to work on the rubbing noise from the fan; that made it possible to slip the old fuel pump out. I plan to replace it with one of the angled alternator units with the shorter push rod. Fuel pumps don't seem to last all that long, and it will be nice to not have to fight with it again.

[realmechanic]

Most people just go with the alternator fuel pump and the shorter rod as is gives more clearance and it will fit both. There is a few aftermarket generator fuel pumps that are short and will fit with the alternator and not rub but its all just personal preference. The plug will work fine, most have used a dime to plug the hole but whatever fits.

[mdege]

Dimes are not always readily available outside of the USA

You just have to come up with something that is available.
_________________
- Michael

1965 21F: Restoration of a former '65 firetruck
1963 Typ3 Notchback project
1988 Multivan Magnum 112i
1984 Standard: My son wanted a bug for his first car

[halfassleatherworks]

you say that it is a 64 bus, the 34 carbs were for dual port motors, if yours is a later motor, make sure it has the right distributor for the carb also and not a 009
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[livingskies]

It's not a dual port engine and it has the 009 distributor in place. Hope that will work with the Solex 34 PICT3 carburetor. If not, I can pull a carburetor off of an older parts vehicle - have several early 1960s vehicles and 1971 bay window donors available.

That raises an interesting issue: Does this bus have a 1300 or a 1500 engine? The first digit of the stamped engine number is indistinct and could be either an 8 or a 0. The engine number is either 8274901 (January 1964 1300 cc production number) or 0274901 (August 1963 1500 cc production number, if I am reading the info in the technical section correctly. My wife says its a 0, while I'm not sure. Would VW have put an engine produced in August into a vehicle produced four or five months later?

Either way, it's a 1964 engine and likely is the original engine for the bus. The bus has a 13 4 production date on the M code tag. The one and three are tight to each other, with a space before the 4. Assuming that means January 3, 1964, although guessing at that. No 216 on the M code plate.

Picture of engine number below. Thoughts? Any other easy ways to tell whether this is a 1300 or 1500 cc engine?

EDIT: Just looked at engine differences on line and discovered that the three piece manifold that this engine has is a 1600 cc feature. I suppose that means that someone in a long past rebuild installed 1600 cc dual port heads on the original block. Old picture of manifold connection and 009 distributor below - cleaner than that now with some parts replaced. Any help with knowing what this is - or isn't - is much appreciated.

[halfassleatherworks]

more the likely its was a 1300 F case 6V flywheel system. only thing different between 13 and 15 is bore size 77 vs 83
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Belts, wallets, mouse pads, drink coasters, Engraving, most things made in leather.

personal items if you want it in leather in Reno Nv, *****

[Eric&Barb]

Being that the engine has dual port intake manifold, it is probably now a 1600cc, but could be bigger. "F" engine was very much not original to a split screen bus.

Stop dumping fuel down the carb throat and FILL the carb float chamber with fuel.
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[Eric&Barb]

[Eric&Barb]

https://www.thesamba.com/vw/forum/viewtopic.php?t=723596&highlight=fuel+proof+funnel
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[livingskies]

Thanks guys for the help. I agree that pouring a little gas (an ounce or less) down the carburetor may not be the best practice - should not have mentioned that. I learned that trick from the grade school dropout car guys that I hung around with at age 14. I do keep a couple of fire extinguishers handy and would never consider pouring gas while turning the engine.

I ordered a new fuel pump, which is on the way. In the meantime, I got impatient and did a temporary hookup of a low pressure electric fuel pump that I have as a backup for an Austin Healey. The bus did start and I let it run for about five minutes.

I can't say that it ran great, but it did run. Playing with carburetor settings and timing. The starter also does not sound great - it's a 6 volt starter, and a 12 volt starter may be needed sooner than later. Also took the 6 volt coil off and installed a 12 volt coil.

Wondering what the correct timing - both static and running - should be for this engine that may now be a 1600 cc engine. Some late 60s 1600s require 0 degrees static advance. Or is 7.5 or 10 degrees a better bet for this somewhat unknown parts engine?

[Eric&Barb]

[livingskies]

Went back out after a break of a few hours and went at it again. With the new 12 volt coil and temporary electric fuel pump in place, it now starts at the touch of the key, sounds good, and idles reasonably well. The starter also seemed fine, now that it does not have to crank much.

I set the timing first with a test light and then with a dial back timing light. It runs best with static timing and timing at idle of 10 degrees and about 28 or 30 degrees with full advance at higher rpm.

The carburetor still can use some fine tuning, and suggestions are appreciated. The idle air mixture screw has a large range where adjustments don't make any noticeable difference - it runs OK from 2 1/2 to 4 1/2 turns out. I set it at about 3 1/2 turns out. The air bypass screw also has a range of half a turn out to about four turns out where it runs OK. As one backs that big screw out more than that the idle speeds up quite a lot. So I set that at about three turns out. Still needs more work, I'm sure.