Dual Carbs Question

[OrangeMango]

Hello everyone,

I bought these dual carbs from someone on marketplace, they have strange looking intakes and wondering is anyone has seen them before. He said he couldnt get them to sync up properly and upgraded to some webbers. This will be my first time messing with dual carbs and will need to order a linkage kit so I wont be installing and messing with them yet. The fuel inlet looks a little large for the stock tubing so I probably will downsize it, any reason I shouldn't? He said he rebuilt them prior to me buying them but I have a spring attached on one of them to a bolt and the other doesn't. I'm going to have to do some more research but if anyone can point out anything odd that I should look at?

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1972 Super Beetle stock 1600 DP
1967 Karmann Ghia stock 1500 SP

[otis_bartleh]

Those look like Kadrons. I don't use the stock Kadron linkage, I use one that is similar in style to the CSP linkage. I got mine from Kaddyshack, but I can not recommend them from my personal experience.

That spring from the linkage to the screw on top is to help the throttle return closed, they're on both of mine, on my bus engine.
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-Adam
'59 Mango Bus
'69 Bug - Cobalt Blue

[OrangeMango]

[Rome]

I agree that those are Kadrons, also known as Brosol 40's (Brazilian Solex). In your 2nd photo you can see the letters "SOL" on the carb body just behind the nut for the manifold attachment.

The manifolds are one version of Kadrons, being steel. The other type are aluminum. The curved pipe on each manifold is for the vacuum equalizer "balance" tube. Use a sturdy hose for those such as the reinforced stock-style 1/2" ID air filter breather hose.

You can de-rust those manifolds by sandblasting, or soaking them in white vinegar overnight. Or also Evapo-Rust.

Kads originally had small metal ball studs at both throttle levers. They snapped into a ball socket at each end of the original Kad crossbar linkage. The linkage worked reasonably well as long as those ball sockets did not develop any slop from wear and lack of lubrication. Your throttle arms do not have those ball studs, which were press-fit and peened into the arms. However, there are slightly better solutions for linkages, such as the Scat center mount swivel, the Gene Berg style with "down rods" ($$), and the "CSP"-style center mount swivel.

The idle jet is seen in the first photo. It's brass and has a hex-shaped head. Use an 8mm wrench to remove it. You should be able to read the jet size after you remove it, stamped in tiny numbers. Typical size is 55.

If you have original style air filter assemblies, they have a single mounting stud. That stud is mounted off-center on the air filter, so that once you have the carbs on the engine you can rotate the entire air filter to clear the fan shroud and have the most clearance between the engine compartment side panels and the front firewall.

[cletus_zuber]

Go to Kaddieshack.com and read his tech articles and videos, lots of info there.
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1972 1302
HPMX 40's & 019

[gt1953]

here is a photo of my kadrons and linkage...have blow it up.

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Volkswagen: We tune what we drive.
Numbers Matching VW's are getting harder to find. Source out the most Stock vehicle and keep that way. You will be glad you did.

72 type 1
72 Squareback
({59 Euro bug, 62, 63, 67, 68, 69, 73 type ones 68 & 69 type two, 68 Ghia all sold})

[MI-Bug]

I too am running a set of those Kadrons. Fairly simple carbs to use and tune. There is a book out there with tons of good info and I highly recommend you grab a copy. I'm using the SCAT linkage and like it.

[volksworld]

one of the design issue with Kadrons is the discharge hole where the idle mixture exits the carb is on the side with the mixture screw...so as a result more of the fuel mixture goes down the manifold port into the cylinder closest to that screw....so they tend to idle on those 2 cylinders which could be what the PO means when he claimed he couldnt syncronize them...they are very sensitive to fuel pressure(needs to be low) and they'll also drip out of the pump nozzles if not set up correctly...been a while but found a lot of good info on AJ Sims LowBugget site...with the built-in air cleaner stud you'll need a piece of tubing to stand on top of the carb io use a Uni-Syn

[otis_bartleh]

[OrangeMango]

Thanks for the all responses, I stopped getting email updates and didn't know anyone else replied. I will look into the sites and try to figure out how to set everything up properly.
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1972 Super Beetle stock 1600 DP
1967 Karmann Ghia stock 1500 SP

[wcfvw69]

[heimlich]

Dual Kadrons with a 019 would be a good way to go.
_________________
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[wcfvw69]

If you're going to run a mechanical advance only distributor with those dual Kadrons, run a Bosch 009 or Bosch 010. The 010 would be first choice though they are expensive.

I ran a high compression 1835 with dual Kadron's, a German Bosch 009, dual mufflers in a cal look VW bug back in the mid-1980's. I ran low 14 second quarter mile runs with it.

I would never run a 019 in a bug. It has a short ramp rate and only advances to maybe 15-16 degrees. The 019 is basically a BR8 late 50's bus distributor. Those split buses also used reduction boxes and had a max speed of what? 50-55 mph?
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40+ years of VW repair, and VW parts and vehicle restoration experience.
The Samba member since 2004.

**Now rebuilding throttle bodies for VW's and Porsche's**
**Restored German Bosch distributors for sale or I can restore yours**
**Restored German Pierburg fuel pumps for sale or I can restore yours**
**Restored Porsche fuel pumps or I can restore yours**
**Restored Porsche distributors or I can restore yours**

[OrangeMango]

So I made a trip down to socal and picked up the linkage, heat riser block offs. I had some time this weekend to look at everything and noticed a few things I though I should ask about.
1st the bolts on these on the inside look to be cut, assuming to fit through the hole, is this normal? I feel like it would be easier to run a bolt going down and a nut at the bottom
2nd the idle jet on one of them looks rusted up, I will pull this off and take a look but might just need to replace it.
3rd the fuel inlets are 2 different sizes, this is not normal right? One is reading at about 4mm inside diameter and the other about 5.6mm inside diameter.

Between the idle jet and the different size fuel inlets I can see why he might have been having a hard time syncing them up.

Lastly is it possible to run these with a vacuum advance distributor and capping off the vacuum port? I will buy a different distributor, I just want to see if I can get them installed and idling without replacing it right now.

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1972 Super Beetle stock 1600 DP
1967 Karmann Ghia stock 1500 SP

[heimlich]

Kadrons have to be modified to add the vacuum port to them. If you can add the vacuum port you can get a 034 distributor.
_________________
www.vwnos.com [email protected]
Classic Brands. Classic Quality.
Not all parts are made the same. NOS OE/OEM parts made mainly in West Germany, Early Germany, and Early Brazil are where VW produced the best quality parts and best fitting products.
5% Off your order with coupon code: 5%OFF
Restored Distributors Available (<--Click here)

[Rome]

[wcfvw69]

I ran a high compression 1835 in the early 1980's with dual Kadrons, dual mufflers and a Bosch 009 mechanical advance only distributor. That engine did low 14's in the quarter mile. The 009 worked great with that set up.


You don't have to run an SVDA with those carbs. A 009 or even better, a 010 works very nicely with those carbs.
_________________
Contact me at [email protected]
Follow me on instagram @sparxwerksllc

40+ years of VW repair, and VW parts and vehicle restoration experience.
The Samba member since 2004.

**Now rebuilding throttle bodies for VW's and Porsche's**
**Restored German Bosch distributors for sale or I can restore yours**
**Restored German Pierburg fuel pumps for sale or I can restore yours**
**Restored Porsche fuel pumps or I can restore yours**
**Restored Porsche distributors or I can restore yours**

[Rob Combs]

One of the reasons people have trouble synchronizing Kadrons is because the linkage that comes in the kit is horrible; at least the set of Kadron linkage that came in my kit 25 years ago did. At the time I couldn't understand why. My understanding is that that linkage set never improved.

The ball ends will start popping off at random in a short timeframe (at least mine did). Then there is the issue of both carb arms attaching on the same side of the pivot, meaning the linkage between the carbs is a fixed length, while your engine is not - due to thermal expansion and contraction. This doesn't seem like it would matter that much but it has more of an effect on synchronization than a lot of people would believe, and is even worse if you're not running a thermostat to keep the engine width pretty stable.

Your linkage arms at the carbs look very much like those that come with the Scat universal linkage kit; maybe that's what the PO tried out. By the nature of its design, it too suffers from the fixed-length issue. I spent a lot of time and effort trying to work around this on my Scat universal kit, with no success.

If you're going to run a center-mount linkage, consider one that mounts the carb arms one on either side of the pivot, that way when the engine width changes, the center pivot just twists a little and self-compensates for the width variation. This will go a long way toward holding synchronization. Just make sure it's designed in such a way that the geometry between the center pivot and the carbs holds very close to the same angularity on both sides. Otherwise they'll synch up somewhere in the range of motion but not hold that synchronization throughout the throttle travel. Intake manifold height and center pivot height will both come into play here, and it may be difficult to get it right.

I may catch a little hate for this one, but although pricy and not exactly perfect, the Berg linkage will get you really close to having carbs that will synchronize and stay that way. They're fairly easy to get the linkage rods geometrically similar, and don't suffer nearly as much from engine width variation. Just read and understand the installation instructions - they are a little difficult to follow when they describe bending your brand new linkage to finalize synchronization, but if you think through it before actually bending anything it will make sense.

When I ran duals, the Berg was my third and last linkage kit. It was the best solution for my no-thermostat engine.

Hope this is helpful.