I have been driving and working on ’67 Beetles for over 37 years. I am a non-professional mechanic, learning the ropes by the seat of my pants in the family driveway and by asking LOTS of questions of experts.
Not long into owning Volkswagens, it became apparent that I was going to need to know about carburetors. My VW mechanic, at the time, was obliging, telling me some tricks of the trade. By this time of life (I’m now 74) I thought that I knew the 30 Pict-1 inside and out, by heart, and could work on them in the dark. But…….
That “but” caught me way off-guard. It caught some other people off-guard, as well. Here’s how it happened. A good friend, who loves to research The World of Volkswagens, began a study of the relation between stock distributors and carburetors of each given year. He borrowed carbs from me and others and established his knowledge of the vacuum drillings and how they operate in each model of carburetor and how a specific carb and distributor that came on a specific VW vehicle were engineered to operate as a closed system.
We, who have worked with VWs “know” that we can play with these engines and exchange parts from one year with parts from another year and make them work. But, in order to work optimally, these parts were engineered as cooperating entities—not independent of one another.
And so, I was brought up short when my friend announced to me that there were two versions of the 30 Pict-1 carb for USA import Beetles. I even argued the point. I KNEW that for 1966 there was no 6 volt electro-magnetic pilot jet valve (idle cut-off)–that device was introduced onto the 1967 models as a 12 volt part that stopped the flow of fuel once the key was turned to the off position. It is rather an anti-dieseling device. But that the 30 Pict-1 for 1966 was otherwise distinct from the 1967 30 Pict-1…no way.
Based upon this new information, I dug through my supplies of carbs until I found and separated those from 1966 (1300 engines) and those from the 1967 1500 engines (note that I am speaking about vehicles specifically exported from Germany into the USA through dealerships).
And because we of 1967Beetle.com are concerned with Beetles, and, specifically 1967 Beetles, my comparisons will be limited to the ’66 and ’67 Beetle versions of the 30 Pict-1 carburetors. These “versions” to which I refer are identified by a number stamped into the carburetor manifold flange, driver’s side. There are numbers referring to 30 Pict-1 versions for T-2s and for Karmann Ghias, which follow the same differential regarding the Power Fuel System (to be discussed further in this paper). Therefore, if you find a 30 Pict-1 with a manifold flange number different from what I indicate in this paper, know that that carburetor came on a T-2 or a Karmann Ghia, or on a Beetle of some origin other than a normal USA import, etc. That’s a complicated discussion for some other venue.
Here are the manifold flange numbers which we should expect to find on a 30 Pict-1 carburetor for a USA 1966 Beetle:
- VW 47-1 with the early style throttle return spring
- VW 75-1 with the late style throttle return spring
- VW 83-1 with the late style throttle return spring
Here is the manifold flange number that we should expect to find on a 30 Pict-1 carburetor for a USA 1967 Beetle: VW 105-1
Upon comparing carburetors closely, I had no choice but to agree with the facts.
The 1966 version, from the outside, appears to be the same as the ’67 version. The bodies are cast identically. However, upon closer inspection, one can see that there is a drilling that is not continuous in the ’66 version, whereas the drilling in the ’67 version IS continuous and contributes to what is called the “Power Fuel System”.
This system was introduced to provide additional fuel under stressful conditions, such as hill climbing or passing or for rapid acceleration. It is vacuum activated.
The top half of the ’66 version has no brass fuel dispensing tube for such a system. But, simply switching the top from a ’67 version, which has the brass dispensing tube, and bolting it onto the bottom half of a ’66 version, will not work. This is because, although the casting is present in the ’66 version, it is not drilled through to the bowl—the source of the fuel to be dispensed.
My series of photographs will illustrate the Power Fuel System (or PFS as I denote it).
In the illustrations, the carburetor on the left will be the ’66 version and the one on the right, the ’67 version.
Illustration #1 pictures both German Solex 30 Pict-1 versions. The non-PFS ’66 version, on the left, is stamped “VW 83-1” on the manifold flange. The ’67 version, on the right, is stamped “VW 105-1” on the manifold flange. Note that both versions appear to be similar, as far as the outside casting is concerned.
Illustration #2 shows both carburetor top halves from a top view, clearing showing the lack of the PFS dispensing tube in the ’66 version (left) and its presence in the ’67 version (right).
Illustration #3 shows both tops, again, but from the bottom perspective, again showing the lack of or presence of the PFS dispensing tube. Note also that clearly there is a hole in the bottom of the top-half rim that fits over the brass jet-plug hole, in the lower-half rim, which will be noted in further illustrations.
Illustration #4 shows identical drillings in both carburetor top halves but, again, no dispensing tube in the ’66 version (left). The drilling in the ’67 version (right) matches its dispensing tube.
Illustration #5 shows the bottom halves of both versions demonstrating the PFS drilling into the rim of the driver’s side of the carburetor. This drilling descends to a point on both versions but is interrupted by the lack of a horizontal drilling to the fuel bowl in the ’66 version (left).
Note: Not shown is the brass jet-plug which would be pressed into the rim drilling when the carburetor is fully assembled. Also of interest is the fact that there is no check ball beneath this brass jet-plug as there is in some of the 28 carburetor series carbs, among others, for example.
Illustration #6 shows the driver’s side of the bottom halves of both versions. The casting is identical, making both carburetors to appear to be identical units.
Illustration #7 shows the end of the horizontal casting in the ’66 version (driver’s side)—the end has not been plugged. This means that it has not been drilled, then had the end plugged.
Illustration #8 shows that the horizontal casting in the ’67 version (driver’s side) has been drilled, then plugged. Note the tiny, shiny plug.
Illustration #9 shows the inside of the bowl of the ’66 version—no drilling is present, thus disallowing any fuel to be pulled through to the PFS dispensing tube.
Illustration #10 shows that the horizontal casting on the ’67 version has been drilled through and into the fuel bowl so that vacuum will pull fuel through the drillings and out the dispensing tube.
Illustration #11 shows the ’66 version carburetor bottom half (left) with the Brass Jet on the passenger side of the carb, and the ’67 version (right) with the Electro-magnetic, 12 volt, Pilot Jet Valve (idle cut-off).
Of course, Volkswagen trained and certified specialists knew of all of these differences and didn’t switch carburetors from one car to another unwittingly. Nor did they mismatch tops and bottoms.
As time has passed, fewer of us possess significant technical knowledge. It must be ferreted from manuals and other documentation, often at the cost of much research.
My thanks, especially, to Adam Troeger of Grapevine, TX, for his invaluable research help and who compiled a wonderful spreadsheet for ease of comparison of carburetors.
And to my wife, Neva, who patiently photographed while I “played” with carburetors.
Additional thanks to several who made contributions to:
TheSamba and to Andy T. who compiled data from several sources. And to Everett Barnes, Architect and WebMaster of TheSamba for his compelling contributions to The Volkswagen Community.