TheSamba.com :: View topic - diaphram on 34 PICT-3

Fri Mar 19, 2010 11:13 pm

what does the diaphram on a '71 bus 34 pict-3 carburetor do? It makes the engine idle too high and sputter and miss and have a flat spot accelerating. when I take it off it runs a lot better. It has an 009 distributor, would it run better with a dual vacuum distributor?

Fri Mar 19, 2010 11:35 pm

Diaphram??

A vac advance distributor might make it better. But an 009 can be great also. There have been dozens of discussions on this.

Sat Mar 20, 2010 12:14 am

What does the vacuum canister attached to the carburetor do? It has two vacuum hoses. One hose is from the intake manifold and the other is from the lower/right side of the carburetor.

Sat Mar 20, 2010 6:07 am

Are you talking about the throttle valve positioner?

Sat Mar 20, 2010 9:08 am

You mean this thing?

The thing forum is a 34 pict goldmine... as type 181's come with them stock. I went with a DVDA on mine and it really made a difference. I do carry the .009 in the car, should I ever need a replacement on the road.

Sat Mar 20, 2010 10:16 am

think he is talking about the altitude adjuster or the C.A. carb thing
IE http://www2.cip1.com/ProductDetails.asp?ProductCode=VWC-113-129-031-KCAL

if you are using hoses on that carb with out a svda or dvda block them off.

Sat Mar 20, 2010 10:20 am

I think Jody is correct and the guy is talking about THIS

http://www.thesamba.com/vw/classifieds/detail.php?id=796142

Which if the diaphragm in it is bad and the vac hoses are hooked up it will have a vacuum leak and run like caca... But it also sounds like he could have the usual host of at least a dozen more issues too :lol: :wink:

Sat Mar 20, 2010 11:02 am

this device mechanically slows how fast the carb returns to idle each time you let off the throttle to keep the engine from stalling because the mixture is so lean.

This device holds the RPM up when you let off the throttle but it does so dependent upon altitude the vehicle is at and also looks at the vacuum levels in the engine. This is to reduce smog.

With an 009 just plug off all the vacuum lines. Put a bolt with some silicone on it into a vacuum hose and let it sit 30 minutes. Then slide the other end of the hose onto the vacuum nipples on the carb and manifold.

Sun Mar 21, 2010 12:13 pm

It's the thing keifernet said it was. Took it off and plugged the vacuum supply ports as it didn't seem to do anything.