What is the correct original carb?

[Rick]

Me again guys!! I'm going to try and track down a rebuilt carb for my 1971 AS Vert. A gentleman on the Samba says he has a 281-1 body- which is the correct carb for this car. He will rebuild this body. Before I proceed is this the correct one. Is there a Solex Carb or plate # on the carb for the 1970 AS 34 pict carb. Again guys thanks for the info!


Rick

[Bookwus]

Hiya Rick,

A Solex 34PICT3 with a flange number of 281-1 is, indeed, the correct original carburetor for your 71.

And I would add this..........if the gentleman you are talking to over at TS is Keith (kiefernet) you could not be in better hands.  This guy is the best at reconditioning Solex carbs.  He's a stand-up guy all the way around.

Oh, and about the 1970 carburetor...........  VW introduced the dual port engine with the start of the 1971 model year.  That dual port engine needed a slightly larger carburetor than the single port engines of previous years.  This larger carburetor was the 34PICT3 and 1971 was its first production year.  Prior to 1971 VW had used the 30 series carburetors on their vehicles.  In 1970 the OEM carburetor was the 30PICT3.  Inasmuch as manual and AS carbs were nearly identical, there was no flange number for the 30PICT3 in 1970.  The only difference between the 30PICT3 on a manual and a 30PICT3 on an AS was that the AS carburetor had no throttle positioner.

[68autobug]

Hi

what is a throttle positioner Mike.. ?

I haven't heard that term before...

Our carbies with no pollution stopping items on them
seem to work OK...

If You bought a new Carburetor in the US Mike,
would it have any emission controls on it??

LEE

[Bookwus]

Hiya Lee,

The throttle positioner is an emissions type device.

With the appearance of the 30PICT3 in the 1970 production year VW engineers realized that they would have to come up with something if they were to meet the Clean Air requirements just being enacted in the USA.  That's where the throttle positioner makes it debut.

Basically, A throttle positioner is activated by engine vacuum, and actually has an arm that connects to the throttle lever and can prevent the throttle from completely closing, depending on the engine load and vacuum conditions.  Some call it a deceleration valve.  It allows air to get into the combustion chamber via the intake manifold thereby reducing emissions.  Or so the theory goes.

It was usually mated up with an altitude compensater and in 1970 and 71 the altitude compensater portion of this assembly was separated from the throttle positioner.  The throttle positioner was attached to the carburetor and the altitude compensater was mounted on the firewall.  The two units were connected by a hose.  And in 1971 VW also installed a dashpot on the 34PICT3 to assist in the throttle closing operation.

Actually Lee, this is mostly all ancient history.  In all of my experience with VWs I have never seen the throttle positioner and the altitude compensater installed and functioning.  Most of these units were out of the cars pretty fast, although it's common to find bits and pieces of them in cars today.

New carbs (for VW anyway) bought in the USA are bone stock generics.  No emissions bells and whistles.   

[68autobug]

Hi Mike,
Very interesting information..
as i said i've never seen these on any beetles in Australia
whether any actually came with them in 1975-76
I'm not sure...
I know Japanese cars had dashpots in the 70s...
as i used to disconnect them or take them off alltogether
and they were still being used in the 80s..
I suppose they were on all Japanese cars until Fuel injection arrived...
and We never did have any fuel injection beetles either..

the only fuel injection Volkswagen was the later model type 3 Fastback TLE

cheers Mike

Lee